Chemical Bonding and Molecular Structure – MCQ Answers
Page 1
1. The hybrid state of S in SO₃ is similar to that of
Answer: d) C in CO₂ (Both have sp² hybridization)
2. The hydration energy of Mg²⁺ is larger than that of:
Answer: b) Na⁺ (Mg²⁺ has higher charge density than Na⁺)
3. Number of lone pair(s) in XeOF₄ is/are
Answer: b) 1 (Xe has one lone pair, square pyramidal shape)
4. Van der Waals’ forces between molecules depend upon:
Answer: d) All of these
5. XeF₆ is:
Answer: b) Pentagonal pyramidal (sp³d³ hybridization, distorted)
6. The bond order in NO is 2.5 while that in NO⁺ is 3. Which of the following statements is true?
Answer: b) Bond length in NO is greater than in NO⁺ (Higher bond order = shorter bond)
7. An atom with atomic number 20 is most likely to combine chemically with the atom whose atomic number is:
Answer: b) 16 (Ca (Z=20) combines with S (Z=16) to form CaS)
8. Which has the largest distance between the carbon-hydrogen atom?
Answer: a) Ethane (C-H bond length ~1.09 Å, sp³ C-H longest)
9. Length of hydrogen bond ranges from 2.5Å to:
Answer: a) 3.0 Å
10. If H-X bond length is 2.00 Å and H-X bond has dipole moment 5.12×10⁻³⁰ C-m, the percentage of ionic character in the molecule will be
Answer: b) 16% (Using % ionic = (observed/calculated) × 100)
11. Which molecule is planar?
Answer: c) C₂H₄ (sp² hybridized, trigonal planar at each carbon)
12. From the molecular orbital theory, one can show that the bond order in F₂ molecule as
Answer: b) 1 (F₂: BO = (8-6)/2 = 1)
13. Two ice cubes are pressed over each other until they unite to form one block. Which one of the following forces dominates for holding them together?
Answer: c) Hydrogen bond formation
14. Maximum number of covalent bonds between two like atoms can be:
Answer: a) Three (Maximum triple bond between two atoms)
15. When sodium and chlorine react, energy is:
Answer: a) Released and ionic bond is formed
16. The maximum possible number of hydrogen bonds a H₂O molecule can participate in is
Answer: d) 4 (Two donor and two acceptor sites)
17. The element having lowest ionisation energy among the following is:
Answer: b) 1s²,2s²2p⁶,3s¹ (Na – alkali metal, lowest IE)
Page 2
19. Two types FAF angles are present in which of the following molecules? (X=S, Xe, C)
Answer: a) SF₄ (See-saw shape has two different F-S-F angles)
20. The bond angle between two hybrid orbitals is 105°. The percentage of s-character of hybrid orbital is between
Answer: c) 22-23% (Using cosθ relationship)
21. Which is electron deficient compound?
Answer: b) B₂H₆ (Diborane – electron deficient, has 3-center-2-electron bonds)
22. CCl₄ is insoluble in water because:
Answer: a) CCl₄ is non-polar and water is polar (Like dissolves like)
23. Which of the following is not correct regarding the properties of ionic compounds?
Answer: c) Ionic compounds in their molten and aqueous solutions do conduct electricity
24. The number of sigma and pi (π) bonds present in benzene respectively are
Answer: a) 12 σ bonds, 6 π bonds
25. Which of the following is not tetrahedral?
Answer: c) CO₃²⁻ (Trigonal planar, sp² hybridized)
26. In PCl₅ molecule, P is:
Answer: d) sp³d-hybridized (Trigonal bipyramidal)
27. The bond angle and % of d-character in SF₆ are
Answer: b) 90°, 33% (sp³d², d-character = 2/6 × 100 = 33.3%)
28. Linear combination of two hybridized orbitals, belonging to two atoms and each having one electron leads to:
Answer: a) Sigma-bond
29. In allene structure, three carbon atoms are joined by:
Answer: c) Two σ-and two π-bonds
30. Geometry of SiO₄²⁻ anion is
Answer: a) Tetrahedral
31. The carbon atom in graphite is:
Answer: a) sp²-hybridized
32. Boron cannot form which one of the following anions?
Answer: a) BF₆³⁻ (Boron cannot expand octet, no d-orbitals)
33. If the ionic radii of K⁺ and F⁻ are about 1.34 Å each, then the expected values of atomic radii of K and F should be respectively:
Answer: b) 2.31 and 0.64 Å (Cation smaller, anion larger than neutral atom)
34. If Z-axis is the molecular axis, then π-molecular orbitals are formed by the overlap of
Answer: d) px + px (Sideways overlap perpendicular to bond axis)
35. Which one is the weakest bond?
Answer: a) Hydrogen bond (weakest among these)
Page 3
36. The total number of valency electrons for PO₄³⁻ ion is:
Answer: a) 32 (P=5 + O×4=24 + 3 = 32)
37. The ratio of σ and π-bonds in benzene is:
Answer: a) 2 (12σ/6π = 2)
38. The geometry of PF₅ molecule is:
Answer: c) Trigonal bipyramidal
39. Which one of the following linear structure?
Answer: b) I and V (I₃⁻ and N₃⁻ are linear)
40. According to MO theory, which ranks the nitrogen species in terms of increasing bond order?
Answer: c) N₂²⁻ < N₂⁻ < N₂ (N₂ has BO=3, N₂⁻ BO=2.5, N₂²⁻ BO=2)
41. The equilateral triangle shape has:
Answer: b) sp²-hybridization (Trigonal planar)
42. Which of the following has fractional bond order?
Answer: d) H₂⁻ (BO = 0.5)
43. For which of the following hybridization the bond angle is maximum?
Answer: b) sp (180° angle, maximum)
44. Experiment shows that H₂O has a dipole moment whereas CO₂ does not. Point out the structures that best illustrate these facts.
Answer: H₂O is bent, CO₂ is linear (symmetrical)
45. In TeCl₄, the central atom tellurium involves
Answer: b) sp³d hybridization (See-saw shape)
46. Stability of hydrides generally increases with:
Answer: a) Increase in bond angle
47. Which of the following is isoelectronic with CO₂?
Answer: c) N₂O (Both have 22 electrons)
48. Which can be described as a molecule with residual bonding capacity?
Answer: d) BeCl₂ (Electron deficient, can accept electron pair)
49. Lattice energy of an ionic compound depends upon
Answer: a) Charge on the ion and size of the ion
50. Identify the correct statement concerning the structure of CH₂=C=CH₂
Answer: c) The molecule is non-planar with the two CH₂ groups being in planes perpendicular to each other (Allene)
Page 4
52. Among the following elements, the most electronegative is:
Answer: d) Fluorine (Highest electronegativity, 4.0)
53. Metallic bonds do not play a role in:
Answer: c) Germanium (Semiconductor, has covalent bonds)
55. H₂O boils at higher temperature than H₂S because it is capable of forming:
Answer: c) Hydrogen bonds
56. When two atomic orbitals combine, they form:
Answer: b) Two molecular orbitals (One bonding, one antibonding)
57. The correct increasing covalent nature is:
Answer: a) NaCl < LiCl < BeCl₂ (Covalent character increases with charge density)
58. IP₁ and IP₂ of Mg are 178 and 348 kcal mol⁻¹. The energy required for Mg → Mg²⁺ + 2e⁻ is:
Answer: b) +526 kcal (178 + 348 = 526)
59. The electronic configuration can be assigned to
Answer: c) O₂⁻ (Has one unpaired electron in π* orbital)
60. Some properties of NO₃⁻ and H₃O⁺ are described. Which one is correct?
Answer: a) Dissimilar in hybridization for the central atom with different structure (NO₃⁻: sp² planar; H₃O⁺: sp³ pyramidal)
62. Greater the dipole moment:
Answer: a) Greater is the ionic nature
63. H-B-H bond angle in BH₄⁻ is:
Answer: c) 109° (Tetrahedral, 109.5°)
Page 5
65. The common feature among the species CN⁻, CO and NO⁺ are:
Answer: a) Bond order three and isoelectronic (All have 14 electrons, BO=3)
66. Hydrogen bonding is maximum in
Answer: a) C₂H₅OH (Alcohol has O-H bond for H-bonding)
67. The O-H bond distance in water molecule is:
Answer: c) 0.96 Å
68. O₂²⁺ has a bond order of
Answer: c) 3 (BO = (10-4)/2 = 3)
69. Which among the following molecules/ions is diamagnetic?
Answer: c) Carbon molecule (C₂ is diamagnetic)
70. The enolic form of acetone contains
Answer: a) 9 sigma bonds, 1 pi bond and two lone pairs
71. Which of the following are isoelectronic and isostructural?
Answer: a) NO₃⁻, CO₃²⁻ (Both have 32 electrons, trigonal planar)
72. Which of the following is paramagnetic with bond order 0.5?
Answer: b) H₂⁺ (BO=0.5, unpaired electron)
73. Water has high heat of vaporization due to:
Answer: b) H-bonding
74. The C-H bond distance is the longest in
Answer: a) C₂H₆ (sp³ C-H bond longest)
75. If the electronegativity difference between two atoms A and B is 2.0, then the percentage of covalent character in the molecule is
Answer: b) 46% (Using Hannay-Smith equation: %ionic = 16(ΔEN)+3.5(ΔEN)²)
76. Structure of ICl₂⁻ is:
Answer: c) Square planar (Actually linear, sp³d with 3 lone pairs)
77. Polar covalent compounds are soluble in:
Answer: a) Polar solvents (Like dissolves like)
78. N₂O is isoelectronic to CO₂ and N₃⁻. Which is the structure of N₂O? 
Answer: N≡N⁺-O⁻ (Linear structure)
79. Which does not show hydrogen bonding?
Answer: d) Liquid HBr (HBr does not form H-bond)
80. All bond angles are exactly equal to 109°28′ in
Answer: d) Carbon tetrachloride (Perfect tetrahedral, all bonds identical)
81. Which among the following has highest ionic radius?
Answer: a) F⁻ (Largest among these isoelectronic species)
Page 6
83. The number of electrons involved in the bond formation of N₂ molecule
Answer: c) 6 (Triple bond = 6 electrons)
84. Which one of the following orders is not in accordance with the property stated against it?
Answer: b) F₂ > Cl₂ > Br₂ > I₂ : Bond dissociation energy (F-F bond is weaker than Cl-Cl)
85. What is the dominant intermolecular force or bond that must be overcome in converting liquid CH₃OH to a gas?
Answer: b) Hydrogen bonding (Methanol has O-H bond)
86. The incorrect statements regarding bonding molecular orbitals because:
Answer: b) Bonding molecular orbitals have high electron density between the two nuclei
87. A coordinate bond is a dative covalent bond. Which of the below is true?
Answer: c) Two atoms form bond and one of them provided both electrons
88. The bond length between C-C bond in sp² hybridised molecule is
Answer: c) 1.33 Å (C=C bond length in alkenes)
89. The electronegativity values of C, H, O, N and S are 2.5, 2.1, 3.5, 3.0 and 2.5 respectively. Which bond is most polar?
Answer: d) O-H (ΔEN = 3.5 – 2.1 = 1.4, highest)
90. Which of the following has largest size?
Answer: a) Al (Neutral atom is largest)
91. In which of the following, the bond length between hybridised carbon atom and other carbon atom is minimum?
Answer: a) Propyne (C≡C triple bond shortest)
92. Which is expected to conduct electricity?
Answer: c) Molten KCl (Ions free to move)
93. Metals are good conductors of electricity because they contain
Answer: d) Free electrons (Sea of electrons model)
94. The species having pyramidal shape is
Answer: d) OSF₂ (Pyramidal shape)
95. The attraction that non-polar molecules have for each other is primarily caused by:
Answer: d) Van der Waals’ forces
96. In HCHO carbon atom has hybridisation:
Answer: b) sp² (Trigonal planar)
97. Which of the following species has four lone pairs of electrons in its outer shell?
Answer: c) Cl⁻ (Cl has 8 electrons in valence shell, 4 lone pairs)
Page 7
99. Chlorine atom, in its third excited state, reacts with fluorine to form a compound X. The formula and shape of X are
Answer: d) ClF₇, pentagonal bipyramidal
100. The formation of oxide ion O²⁻(g) requires first an exothermic and then an endothermic step. This is because:
Answer: c) O⁻ ion will lead to resist the addition of another electron (Electron-electron repulsion)
101. In which of the following molecules are all the bonds not equal?
Answer: c) ClF₃ (T-shaped, bonds not equivalent)
102. Which of the following compound is covalent?
Answer: a) H₂ (Non-polar covalent)
103. Which of the following molecular species has unpaired electron(s)?
Answer: c) O₂⁻ (Superoxide ion has one unpaired electron)
104. The correct order of bond angles is:
Answer: c) PI₃ < PBr₃ < PCl₃ < PF₃ (Bond angle increases with electronegativity of substituent)
105. If the bond length and dipole moment of a diatomic molecule are 1.25 Å and 1.0 D respectively, what is the per cent ionic character of the bond?
Answer: c) 16.66 (Calculated using % ionic = (μ_obs/μ_calc) × 100)
106. The molecule which does not exhibit dipole moment is
Answer: d) CCl₄ (Symmetrical tetrahedral, zero dipole moment)
107. N₂ accept electron and convert into N₂⁻, where this electron goes?
Answer: a) Antibonding π-molecular orbital (π* orbital)
Page 8
108. The correct order of radii is:
Answer: b) F⁻ < O²⁻ < N³⁻ (Isoelectronic series, radius increases with negative charge)
109. The bond order is maximum in:
Answer: a) H₂ (BO=1, highest among these)
110. Which of the following atoms has minimum covalent radius?
Answer: b) N (Smallest among these in same period)
111. The screening effect of d-electrons is:
Answer: d) Less than p-electrons
112. Which of the following statement is wrong?
Answer: a) Stability decreases from NH₃ to BiH₃
113. The molecule having permanent dipole moment is:
Answer: a) SF₄ (See-saw shape, polar)
114. Unusually high boiling point of water is result of
Answer: a) Intermolecular hydrogen bonding
115. Which of the following is least ionic?
Answer: c) CaI₂ (Largest anion, most covalent character)
116. What bond order does O₂²⁻ have?
Answer: a) 1 (BO = (10-8)/2 = 1)
117. A compound contains X, Y and Z atoms. The oxidation states of X, Y and Z are +2, +2 and -2 respectively. The possible formula is
Answer: b) Y₂(XZ₃)₂ (Charge balance: +4 + (-12) = -8, need further balancing)
118. Which one of the following is a non-polar molecule?
Answer: a) CCl₄ (Symmetrical tetrahedral)
119. Which one has the regular tetrahedral structure?
Answer: c) BF₄⁻ (Tetrahedral, all bonds equivalent)
120. If the dipole moment of toluene and nitro-benzene are 0.43 D and 3.93 D, then what is the expected dipole moment of p-nitro toluene?
Answer: c) 4.36 D (Vector sum: 3.93 + 0.43 = 4.36 D)
121. Which of the following is most stable?
Answer: a) Pb²⁺ (Inert pair effect, most stable)
122. In which of the following compound sp² hybridisation is absent?
Answer: b) CH≡C-CH₂-CH₃ (Has sp and sp³ only)
123. Which one of the following pairs of species has the same bond order?
Answer: b) CN⁻ and NO⁺ (Both have BO=3)
124. Which characteristic regarding halogens is not correct?
Answer: d) Enthalpy of fusion increases with increase in atomic number (Actually decreases)
125. The number of S-S bonds in sulphur trioxide is
Answer: d) Zero (SO₃ has no S-S bonds)
Page 9
126. The low density of ice compared to water is due to
Answer: c) Hydrogen bonding interactions (Open cage structure in ice)
127. Consider the molecules/ions H₂O, NH₄⁺, SO₄²⁻, ClO₄⁻, NH₃. sp³ hybridisation is involved in the formation of
Answer: d) All of these (All have sp³ hybridization)
128. Which of the following compounds has dipole moment approximately equal to that of chlorobenzene?
Answer: b) m-dichlorobenzene (Dipole moment ~1.5 D similar to chlorobenzene)
130. Which of the following is correct?
Answer: a) The number of electrons present in the valence shell of S in SF₆ is 12 (Expanded octet)
131. The number of sigma and pi bonds in peroxodisulphuric acid are respectively
Answer: a) 9 and 4
132. Which is not a paramagnetic species?
Answer: d) O₂²⁻ (Peroxide ion, diamagnetic, all electrons paired)
134. Electron deficient species are known as:
Answer: a) Lewis acids (Electron pair acceptors)
135. The molecule having three folds of axis of symmetry is:
Answer: a) NH₃ (C₃ axis of symmetry)
Page 10
137. Among the following the molecule with the highest dipole moment is
Answer: b) CH₂Cl₂ (Has highest dipole moment among these)
138. Which of the following is not isostructural with SiCl₄?
Answer: c) SCl₄ (See-saw shape, not tetrahedral)
139. A molecule which cannot exist theoretically is:
Answer: c) OF₄ (Oxygen cannot have expanded octet, no d-orbitals)
140. An atom X has three valence electrons and atom Y has six valence electrons. The compound formed between them will have the formula
Answer: c) X₂Y₃ (X³⁺ and Y²⁻ combine as X₂Y₃)
141. Which one is polar molecule among the following?
Answer: d) H₂O (Bent shape, polar)
142. Shape of molecules is decided by:
Answer: a) Sigma bond (Hybrid orbitals determine shape)
143. The shape of carbon dioxide is
Answer: d) Linear
144. The correct ionic radii order is:
Answer: a) N³⁻ > O²⁻ > F⁻ > Na⁺ > Mg²⁺ > Al³⁺ (Correct isoelectronic order)
145. Which is not linear?
Answer: d) H₂O (Bent, not linear)
146. Hybridisation of oxygen in diethyl ether is
Answer: c) sp³ (Tetrahedral geometry around O)
147. What is the effect of more electronegative atom on the strength of ionic bond?
Answer: a) Increases
148. Which of the following two are isostructural?
Answer: a) XeF₂, IF₂⁻ (Both linear)
149. NF₃ is:
Answer: c) Having low value of dipole moment than NH₃ (NF₃ μ=0.2D, NH₃ μ=1.5D)
150. Molecular size of ICl and Br₂ is nearly same, but boiling point of ICl is about 40°C higher than Br₂. This might be due to:
Answer: c) ICl is polar whereas Br₂ is non-polar
151. Which molecule is linear?
Answer: d) CO₂
152. Which of the following shows minimum melting point?
Answer: a) Naphthalene (Molecular solid, low melting point)
153. Which of the following does not have a lone pair on the central atom?
Answer: c) BF₃ (No lone pair on B, only 6 electrons)
Page 11
154. Molecular orbital theory was given by
Answer: c) Mulliken (with Hund)
155. NH₃ has a net dipole moment, but boron trifluoride (BF₃) has zero dipole moment, because:
Answer: d) NH₃ is pyramidal while BF₃ is trigonal planar
156. Proton plays an important role in…bonding.
Answer: b) Hydrogen (Proton is involved in H-bonding)
157. Which represents a collection of isoelectronic species?
Answer: d) N³⁻, F⁻, Na⁺ (All have 10 electrons)
158. An electrovalent compound does not exhibit space isomerism due to:
Answer: d) Non-directional nature of electrovalent bond
159. In which molecule Sulphur atom is not sp³-hybridized?
Answer: b) SF₄ (sp³d hybridized)
160. In which one of the following species, the central atom has the type of hybridization which is not the same as that present in other three?
Answer: d) PCl₅ (sp³d; others are sp³d too but different geometries)
161. The radii of F, F⁻, O and O²⁻ are in the order of:
Answer: d) O²⁻ > F⁻ > O > F
162. The correct order of decreasing second ionisation enthalpy of Ti(22), V(23), Cr(24) and Mn(25) is:
Answer: d) Cr > Mn > V > Ti
163. How many σ and π-bonds are present in given compound Ph-CH=C-C₂H₅|CH₃?
Answer: c) 25 σ and 4 π-bonds
164. C-Cl bond is stronger than C-I bond, because
Answer: a) C-Cl bond is more ionic than C-I (More electronegativity difference)
165. The ICl molecule is:
Answer: c) Polar with negative end on chlorine (Cl more electronegative)
166. Which of the following silver salts is insoluble in water?
Answer: b) Ag₂SO₄ (Silver sulphate is sparingly soluble)
167. Silicon has 4 electrons in the outermost orbit. In forming the bond:
Answer: c) It shares electrons (Covalent bonding)
168. The shape of gaseous SnCl₂ is
Answer: c) Angular (V-shaped, due to lone pair)
169. Chlorine atom tends to acquire the structure of:
Answer: c) Ar (Chlorine has 17 electrons, needs 1 more for Ar configuration)
170. The d-orbital involved in sp³d hybridisation is
Answer: c) d₂²
171. When O₂ is converted into O₂⁺
Answer: d) Paramagnetic character decreases and the bond order increases
Page 12
172. Intramolecular hydrogen bond is present in
Answer: b) α-nitrophenol (Intramolecular H-bond)
173. A pair of compounds which have odd electrons in the group NO, CO, ClO₂, N₂O₅, SO₂ and O₂ are
Answer: a) NO and ClO₂ (Both have odd number of electrons)
174. According to VSEPR theory the repulsion between different pair (lone or bond) of electrons obey the order
Answer: a) lp-lp > lp-bp > bp-bp
175. The bond between two identical non-metal atoms has a pair of electrons:
Answer: b) Equally shared between the two (Non-polar covalent bond)
176. The bond angle in AsH₃ is greater than that in
Answer: b) H₂O (AsH₃ ~92°, H₂O ~104.5°)
177. The correct order of increasing electropositive character among Cu, Fe and Mg is:
Answer: d) Cu < Fe < Mg (Electropositive character: Cu < Fe < Mg)
178. H-O-H bond angle in H₂O is 104.5° and not 109°28′ because of:
Answer: c) Lone pair-lone pair repulsion
179. The bond order in O₂⁺ is equal to bond order in:
Answer: b) CN⁻ (Both have BO=2.5)
180. The electron affinity for inert gases is likely to be:
Answer: c) Zero (Noble gases have stable configuration)
181. The true statements from the following are: 1. PH₅ and BiCl₅ do not exist 2. pπ-dπ bond is present in SO₂ 3. Electrons travel at the speed of light 4. SeF₄ and CH₄ have same shape 5. I₃⁺ has bent geometry
Answer: b) 1,2,5
182. 1,3-butadiene has:
Answer: c) 9σ and 2π-bonds
183. The bond between atoms of two elements of atomic number 37 and 53 is:
Answer: a) Covalent (Rb (37) and I (53) form covalent bond)
184. In methane the bond angle is
Answer: c) 109° (109.5° tetrahedral)
185. One would expect the elemental form of Cs at room temperature to be:
Answer: b) A metallic solid (Alkali metal)
186. Which of the following is false?
Answer: d) Alkyl halides have higher b.p. than corresponding alcohols (Alcohols have higher b.p. due to H-bonding)
Page 13
187. Ionic radii are:
Answer: a) ∝ 1/(effective nuclear charge)
188. Which of the following statements is incorrect?
Answer: c) Any two atomic orbitals can combine to form two molecular orbitals (Only orbitals of same symmetry can combine)
189. Which of the following pairs will form the most stable ionic bond?
Answer: b) Mg and F (Highest charge/radius ratio)
190. Among NaF, NaCl, NaBr and NaI, the NaF has highest melting point because:
Answer: a) It has maximum ionic character
191. The planar structure of BF₃ can be explained by the fact that BF₃ is
Answer: b) sp² hybridised
192. The correct order of bond order value among (i) NO⁻ (ii) NO⁺ (iii) NO (iv) NO²⁺ (v) NO²⁻ is
Answer: c) (v) < (i) < (iv) = (iii) < (ii)
193. The bond between chlorine and bromine in BrCl₃ is:
Answer: d) Polar with negative end on Cl (Cl more electronegative)
194. Which of the following has regular tetrahedral shape?
Answer: c) [BF₄]⁻ (Tetrahedral)
196. PCl₅ exists but NCl₅ does not because:
Answer: a) Nitrogen has no vacant 2d-orbitals
197. In which of the following pairs the two species are not isostructural?
Answer: b) PF₅ and BrF₅ (PF₅ trigonal bipyramidal; BrF₅ square pyramidal)
Page 14
198. The molecule having a pyramidal shape out of the following is
Answer: d) NH₃
199. If Na⁺ ion is larger than Mg²⁺ ion and S²⁻ is larger than Cl⁻ ion, which will be stable soluble in water?
Answer: a) Sodium chloride (Both ions are compatible)
200. An atom of an element A has three electrons in its outermost orbit and that of B has six electrons in its outermost orbit. The formula of the compound between these two will be
Answer: b) A₂B₃ (A³⁺ and B²⁻ combine)
201. The energy of σ2s-orbital is greater than σ*1s orbital because:
Answer: c) σ2s orbital has a greater value of n than σ*1s orbital
202. The bond angle in ammonia molecule is
Answer: c) 106°45′ (Actual bond angle in NH₃)
203. The compound in which the number of dπ-pπ bonds are equal to those present in ClO₄⁻
Answer: c) XeO₄ (Has similar bonding)
204. The correct order of bond angles (smallest first) in H₂S, NH₃, BF₃ and SiH₄ is
Answer: a) H₂S < SiH₄ < NH₃ < BF₃
205. A covalent molecule AB₃ has pyramidal structure. The number of lone pair and bond pair of electrons in the molecule are respectively.
Answer: d) 1 and 3
206. Be in BeCl₂ undergoes
Answer: a) Diagonal hybridisation (sp)
207. Which statement is wrong?
Answer: d) d²sp³-hybrid orbitals are directed towards the corners of a regular octahedron, not tetrahedron
208. In the anion HCOO⁻ the two carbon-oxygen bonds are found to be of equal length. What is the reason for it?
Answer: c) The anion HCOO⁻ has two resonating structures
209. Which of the following molecules has three fold axis of symmetry?
Answer: a) NH₃
210. Oxygen and the oxide ion have the
Answer: a) Same proton number (Both have Z=8)
211. Valence bond theory of metallic bond was given by
Answer: d) Pauling
212. The correct order of second ionisation potential of carbon, nitrogen, oxygen and fluorine is:
Answer: c) O > F > N > C
213. The molecule which has T-shaped structure is
Answer: b) ClF₃
214. As a result of resonance:
Answer: d) All are correct
Page 15
215. The pair of species with the same bond order is:
Answer: d) O₂⁺, NO⁺ (Both have BO=2.5)
216. Which of the following molecules has pentagonal bipyramidal shape?
Answer: c) XeF₆
217. The number of types of bonds between two carbon atoms in calcium carbide is
Answer: a) One sigma, two pi (C≡C triple bond)
218. The bond angle between H-O-H in ice is closest to:
Answer: b) 109°28′ (Ice has tetrahedral arrangement)
219. If a molecule MX₃ has zero dipole moment the sigma bonding orbitals used by M (at. No. < 21) is:
Answer: c) sp²-hybrid (Trigonal planar, symmetrical)
220. Which combination of atoms can form a polar covalent bond?
Answer: b) H and Br (Different electronegativities, non-metal + non-metal)
221. The bond strength in O₂⁺, O₂, O₂⁻ and O₂²⁻ follows the order:
Answer: b) O₂⁺ > O₂ > O₂⁻ > O₂²⁻ (Bond strength ∝ bond order)
222. The shape of XeF₄ molecule and hybridisation of xenon in it are
Answer: c) Square planar and sp³d²
223. In H₂⁻ ion, the bond order is:
Answer: b) 1/2
224. H-bonding is not present in:
Answer: c) H₂S (Sulphur is less electronegative, no H-bonding)
225. In which of the following gaseous molecules, the ionic character of the covalent bond is greatest?
Answer: d) HF (Highest electronegativity difference)
226. The angle between the overlapping of one s-orbital and one p-orbital is:
Answer: c) 109°28′ (sp³)
228. Which is the correct statement about σ and π molecular orbitals?
Answer: b) (ii) and (iii) only
229. Among the following statement, the correct statement about PH₃ and NH₃ is:
Answer: c) NH₃ is a better electron donor because the lone pair of electron occupies sp³-orbital and more directional
230. Which is expected to have linear structure?
Answer: b) CO₂
231. The bond angle in PH₃ is:
Answer: a) Much lesser than NH₃ (PH₃ ~93°, NH₃ ~107°)
Page 16
232. Carnallite in solution in water shows the properties of
Answer: a) K⁺, Mg²⁺, Cl⁻ (Carnallite = KCl·MgCl₂·6H₂O)
233. A simple example of a coordinate covalent bond is exhibited by
Answer: d) H₂SO₄ (Has coordinate bonds in its structure)
234. In the series ethane, ethylene and acetylene, the C-H bond energy is:
Answer: d) Greatest in acetylene (More s-character, stronger bond)
235. In which molecule the van der Waals force is likely to be the most important in determining the m.p. and b.p.?
Answer: a) Br₂ (Non-polar, only van der Waals forces)
236. Identify the wrong statement in the following:
Answer: c) Smaller the positive charge, larger the ionic radius
238. Dipole moment is shown by
Answer: a) cis-1,2-dichloro ethane
239. Compounds formed by sp³d²-hybridization will have configuration:
Answer: b) Octahedral
240. In which molecule are all atoms coplanar?
Answer: c) BF₃ (Trigonal planar)
241. The AsF₅ molecule is trigonal bipyramidal. The hybrid orbitals used by the As atoms for bonding are
Answer: c) s, pₓ, pᵧ, p₂, d₂²
242. The bond order of N₂⁺ is
Answer: c) 2.5 (N₂ has BO=3, N₂⁺ has BO=2.5)
243. CO₂ is isostructural with
Answer: a) C₂H₂ (Both linear)
244. The compound with the maximum dipole moment among the following is:
Answer: c) o-dichlorobenzene (Highest dipole moment among isomers)
245. Which of the following bonds require the largest amount of energy to dissociate?
Answer: c) N≡N bond in N₂ (Strongest triple bond, 945 kJ/mol)
Page 17
247. The type of hybridisation in XeF₄ is
Answer: c) sp³d²
248. What bond order does Li₂ have?
Answer: b) 1
249. Which have zero dipole moment?
Answer: c) Trans-1,2-dichloroethene (Symmetrical, zero dipole moment)
250. Strongest bond is formed by the head on overlapping of:
Answer: c) 2s- and 2s-orbitals (Maximum overlap)
251. Hybridization state of I in ICl₂⁺ is :
Answer: c) sp²
252. Arrange the following compound in order of increasing dipole moment: Toluene (I), m-dichlorobenzene (II), o-dichlorobenzene (III), p-dichlorobenzene (IV)
Answer: a) I < IV < II < III
253. Which has maximum covalent character?
Answer: a) SiCl₄ (Highest charge density on cation, most covalent)
254. Which species does not exist?
Answer: c) (CCl₆)²⁻ (Carbon cannot expand octet)
255. Among the following which has the highest cation to anion size ratio?
Answer: b) CsF (Largest cation, smallest anion)
256. The dipole moment of HBr is 1.6×10⁻³⁰ C-m and interatomic spacing is 1 Å. The % ionic character of HBr is
Answer: b) 10
257. When an element of very low ionisation potential is allowed to react with an element of very high electron affinity, we get:
Answer: b) A strong ionic bond
258. Ionization potential is lowest for:
Answer: d) Alkali metals
259. The orbitals of same energy level providing the most efficient overlapping are:
Answer: b) sp-sp (Maximum s-character, strongest overlap)
260. The covalent compound HCl has the polar character because:
Answer: c) The electronegativity of chlorine is greater than that of hydrogen
261. Identify the non-polar molecule in the set HCl, HF, H₂, HBr
Answer: a) H₂
262. Which one of the following compounds has sp² hybridisation?
Answer: b) SO₂
263. The increasing order of the ionic radii of the given isoelectronic species is:
Answer: b) Ca²⁺, K⁺, Cl⁻, S²⁻
264. Which cannot exist on the basis of M.O. theory?
Answer: d) He₂ (BO=0)
265. Which of the following does not involve covalent bond?
Answer: b) CsF (Ionic bond)
Page 18
267. The electronegativity of A and B are 1.20 and 4.0 respectively. Therefore, ionic character in A-B bond will be
Answer: d) 72.23%
268. During the formation of a chemical bond
Answer: d) Energy decreases
269. The number of ions formed when a molecule of K₄Fe(CN)₆ dissociates is:
Answer: b) 5 (4K⁺ + [Fe(CN)₆]⁴⁻)
270. Pair of species having identical shapes for molecules is
Answer: c) XeF₂, CO₂ (Both linear)
271. An example of a polar covalent compound is
Answer: d) HCl
272. Which is not an exception to octet rule?
Answer: b) SnCl₄ (Follows octet rule)
274. Which of the following species has a bond order other than 3?
Answer: d) O₂⁺ (BO=2.5)
275. Which of the following is planar?
Answer: d) XeF₄ (Square planar)
276. Among the following species, identify the pair having same bond order: CN⁻, O₂⁻, NO⁺, CN⁺
Answer: c) CN⁻ and NO⁺ (Both BO=3)
277. The bond angle and dipole moment of water respectively, are
Answer: c) 104.5°, 1.84 D
278. The correct order of increasing bond angles in the following species is:
Answer: a) Cl₂O < ClO₂ < ClO₂⁻
279. Which compound shows hydrogen bonding?
Answer: a) RCH₂NHCH₃ (Has N-H bond)
280. Chlorine atom differs from chloride ion in the number of:
Answer: c) Electrons (Cl has 17, Cl⁻ has 18)
281. What is the reason for unusual high b.p. of water?
Answer: b) Due to dipole-dipole interactions
282. The increasing order of the first ionization enthalpies of the elements B, P, S and F (lower first) is:
Answer: d) B < S < P < F
283. The IP₁, IP₂, IP₃, IP₄, and IP₅ of an element are 7.1, 14.3, 34.5, 46.8, 162.2 eV respectively. The element is likely to be:
Answer: b) Si (Large jump after 4th ionization indicates 4 valence electrons)
284. Which of the following is paramagnetic?
Answer: a) B₂ (Has 2 unpaired electrons)
285. Ionization potential of Na would be numerically the same as:
Answer: a) Electron affinity of Na⁺
Page 19
286. Which one of the following conversions involve change in both hybridisation and shape?
Answer: c) BF₃ → BF₄⁻ (sp² to sp³, planar to tetrahedral)
287. According to MO theory,
Answer: a) O₂⁺ is paramagnetic and bond order greater than O₂
288. If the molecule of HCl were totally polar, the expected value of dipole moment is 6.12 D, but the experimental value was 1.03 D. Calculate the percentage ionic character
Answer: a) 17 (1.03/6.12 × 100 = 16.8%)
289. The order of first electron affinity of O, S and Se is:
Answer: b) S > O > Se
290. The nodal plane in the π-bond of ethane is located in:
Answer: c) A plane perpendicular to the molecular plane which bisects the carbon-carbon σ-bond at right angle
291. The correct electronegativity order is:
Answer: c) Si, P, C, N (Increasing electronegativity)
292. The pair of species having identical shapes for molecules of both species is
Answer: b) XeF₂, CO₂ (Both linear)
293. Amongst the following, the molecule that is linear is
Answer: b) CO₂
294. Using MO theory predict which of the following species has the shortest bond length?
Answer: a) O₂²⁺ (Highest BO=3, shortest bond)
295. The hybridisation of carbon atom in benzene is?
Answer: b) sp²
296. Bond angle between two hybrid orbitals is 105°. Hybrid character orbital is:
Answer: c) Between 21-22%
297. KF combines with HF to form KHF₂. The compound contains the species:
Answer: c) K⁺ and [HF₂]⁻
298. σ-hydroxy benzaldehyde, although contains enolic group but does not give test of group with FeCl₃ because:
Answer: c) Of intramolecular H-bonding
299. Iron is tougher than sodium because:
Answer: c) Metallic bonds are stronger in iron
300. Correct order of bond angles in NH₃, PCl₃ and BCl₃ is
Answer: d) BCl₃ > NH₃ > PCl₃
301. The number of π-bonds present in propyne is
Answer: d) 2 (Propyne: CH₃-C≡CH has 2 π bonds)
Page 20
302. A bond with maximum covalent character between non-metallic elements is formed:
Answer: a) Between identical atoms (Non-polar covalent, maximum covalent character)
303. The compound in which underlined carbon uses only its sp³ hybrid orbitals for bond formation is
Answer: c) CH₃CH₂OH (Both carbons sp³)
304. Consider compounds (i) chloroethene (ii) benzene (iii) 1,3-butadiene (iv) 1,3,5-hexatriene. All carbon atoms are sp² hybridised in
Answer: a) (i), (ii), (iv) only
305. When ionic compounds get dissolved in water:
Answer: d) All are correct
306. Pick the odd one out (The one having zero dipole moment):
Answer: c) BCl₃ (Zero dipole moment, trigonal planar)
307. Which of the following shows minimum bond angle?
Answer: d) H₂Te (Smallest bond angle, ~90°)
308. Among the following isostructural compounds, identify the compound which has the highest lattice energy
Answer: d) MgO (Highest charges, small size)
309. Which species is diamagnetic in nature?
Answer: b) H₂ (All electrons paired)
310. Which of the following compounds would have the highest boiling point?
Answer: c) CH₃OH (Strong H-bonding)
311. Hybridisation of central atom in NF₃ is
Answer: a) sp³
312. Which of the compounds has highest boiling point?
Answer: d) Ethanol (Strongest H-bonding among these)
313. The number and type of bonds between two carbon atoms in CaC₂ are:
Answer: b) One sigma (σ) and two pi (π)-bonds (C≡C triple bond)
314. Which of the following hydrogen bonds are strongest in vapour phase?
Answer: a) HF—HF (Strongest H-bond)
315. The bond angle and hybridization in ether (CH₃OCH₃) is:
Answer: c) 110°, sp³
316. Which has the highest bond energy?
Answer: b) Triple bond
317. Among the following compounds the one that is polar and has central atom with sp²-hybridisation is:
Answer: a) H₂CO₃ (Polar, central C sp²)
318. The incorrect statement among the following is:
Answer: b) The second ionization potential of Mg is greater than the second ionization potential of Na (Actually Mg has higher IP₂ than Na)
Page 21
320. The number of electrons in the valence shell of sulphur in SF₆ is
Answer: a) 12 (Expanded octet)
321. Acetic acid exists as dimer in benzene due to:
Answer: b) Hydrogen bonding
322. The correct order of hybridization of the central atom in the following species NH₃, [PtCl₄]²⁻, PCl₅ and BCl₃ is:
Answer: b) sp³, dsp², dsp³, sp²
323. Chemical bond formation takes place when?
Answer: b) Forces of attraction overcome forces of repulsion
324. NH₃ has higher boiling point than expected, because:
Answer: b) It has strong intermolecular hydrogen bonds
336. The half of the difference between the number of electrons in bonding molecular orbitals and antibonding molecular orbitals is known as:
Answer: a) Bond order
337. Which of the following set contains species having same angle around the central atom?
Answer: d) BF₃, BCl₃, BBr₃ (All trigonal planar, 120°)
338. At ordinary temperature and pressure, among halogens, chlorine is gas, bromine is liquid and iodine is solid. This is because:
Answer: b) Intermolecular forces among molecules of chlorine are the weakest and those in iodine are the strongest
339. Which of the following has lowest bond angle?
Answer: b) H₂O (104.5°, lowest among these)
340. Which of the following has shortest carbon-carbon bond length?
Answer: d) C₂H₂ (Triple bond, shortest)
341. Which one of the following constitutes a group of the isoelectronic species?
Answer: b) NO⁺, C₂²⁻, CN⁻, N₂ (All have 14 electrons)
342. The sp³d² hybridisation of central atom of a molecule would lead to
Answer: d) Octahedral geometry
343. Methanol and ethanol are miscible in water due to:
Answer: b) Hydrogen bonding character
344. The shape of ClF₃ is
Answer: a) Distorted T-shape
Page 22
345. Which are true statements among the following? (1) PH₅ and BiCl₅ do not exist (2) pπ-dπ bonds are present in SO₂ (3) Electrons travel with speed of light (4) SeF₄ and CH₄ has same shape (5) I₃⁺ has bent geometry
Answer: b) 1,2,5
346. The actual geometry of NO₂⁻ is
Answer: c) V-shape (Bent)
347. Which has the lowest anion to cation size ratio?
Answer: d) CsF (Largest cation, smallest anion)
348. The energy change accompanying the process Na⁺(g) + Cl⁻(g) → NaCl(s) is:
Answer: d) Lattice energy
349. Which of the following has covalent bond?
Answer: b) AlCl₃ (Covalent, especially in anhydrous form)
350. The correct order in which the O-O bond length increases in the following is
Answer: a) O₂ < O₃ < H₂O₂
351. N₂ is less reactive than CN⁻ due to
Answer: c) Absence of dipole moment
Page 23
352. According to molecular orbital theory for O₂⁺
Answer: b) Bond order is more than O₂ and O₂⁺ is paramagnetic
353. As compared to covalent compounds, electrovalent compounds generally have:
Answer: b) High melting points and high boiling points
354. Which is present in peroxides?
Answer: c) O₂²⁻
355. Two hybrid orbitals have a bond angle of 120°. The percentage of s-character in the hybrid orbital is nearly
Answer: b) 33% (sp² = 1/3 s-character = 33.3%)
356. Which molecule is T-shaped?
Answer: d) ClF₃
357. Which of the following is paramagnetic?
Answer: a) O₂
358. Dipole moment is highest for:
Answer: c) CHF₃ (Highest dipole moment among these)
359. Which will not conduct electricity?
Answer: d) KCl in solid state (No free ions)
360. The ionization potential order for which set is correct?
Answer: a) Li > K > Cs
361. The bond that determines the secondary structure of a protein is:
Answer: c) Hydrogen bond
362. Molecular orbital theory was developed mainly by
Answer: b) Mulliken
363. Which species has lone pair on central atom?
Answer: d) H₂O
364. In which of the following molecules/ions are all the bonds not equal?
Answer: a) SF₄ (See-saw, bonds not equivalent)
365. Super octet molecule is:
Answer: a) ClF₃ (Has 10 electrons around Cl)
366. The number of unpaired electrons in a paramagnetic diatomic molecule of an element with atomic number 16 is:
Answer: c) 2 (S₂ has 2 unpaired electrons)
367. Which of the following statement is not correct?
Answer: d) dsp³ hybrid orbitals are all at 90° to one another (Actually sp³d has 90° and 120° angles)
368. Which statement is correct?
Answer: a) Pi-bond always exists with sigma-bond
Page 24
369. Which of the following pair has same structure?
Answer: d) NH₄⁺ and SO₄²⁻ (Both tetrahedral)
370. Which of the following has dipole moment?
Answer: c) NH₃ (Pyramidal, polar)
371. Which one of the following is highest melting halide?
Answer: c) AgF (Most ionic, highest melting point)
372. The hybridisation state of central atom in PCl₅ is
Answer: a) sp³d
373. The correct order of increasing bond angles in the following triatomic species is:
Answer: a) NO₂⁻ < NO₂ < NO₂⁺
374. K⁺, Cl⁻, Ca²⁺, S²⁻ ions are isoelectronic. The decreasing order of their size is:
Answer: a) S²⁻ > Cl⁻ > K⁺ > Ca²⁺
375. As the s-character of hybridization orbitals increases, the bond angle:
Answer: a) Increases
376. AlCl₃ is covalent while AlF₃ is ionic. This fact can be justified on the basis of
Answer: d) Fajan rule
377. Which one of the following is a correct set with respect to molecule, hybridisation and shape?
Answer: c) BCl₃, sp², triangular planar
378. In BrF₃ molecule, the lone pairs occupy equatorial positions to minimize
Answer: c) Lone pair-lone pair repulsion and lone pair-bond pair repulsion
379. The correct order of decreasing polarity is
Answer: b) HF > H₂O > SO₂ > NH₃
Page 25
389. The compounds have been arranged in order of their increasing thermal stabilities. Identify the correct order: K₂CO₃ (I), MgCO₃ (II), CaCO₃ (III), BeCO₃ (IV)
Answer: b) IV < II < III < I
390. Which of the following will show least dipole moment?
Answer: a) Ethane (Zero dipole moment)
391. Which has the minimum bond energy?
Answer: c) I-I (Weakest bond among these)
392. The polarising ability of which one of the following is highest?
Answer: a) Small highly positive ion
393. Which is expected to show paramagnetism?
Answer: a) ClO₂ (Has unpaired electron)
394. Highest covalent character is found in which of the following?
Answer: c) CaI₂ (Largest anion, most covalent)
395. The molecule which has zero moment is
Answer: c) BF₃ (Zero dipole moment)
396. Hydrogen bond is strongest in
Answer: c) F-H···F (Strongest H-bond)
397. The only molecule having dipole moment is
Answer: b) trans-2-pentene (Has dipole moment due to unsymmetrical structure)
Page 26
402. Which is not characteristic of π-bond?
Answer: b) π-bond is formed from hybrid orbitals
403. A molecule in which sp²-hybrid orbitals are used by the central atom in forming covalent bond is:
Answer: b) SO₂
404. Which species has the highest bond order?
Answer: c) N₂ (BO=3)
405. Molecular shapes of SF₄, CF₄, XeF₄ are
Answer: d) Different with 1, 0 and 2 lone pair of electrons respectively
406. The correct sequence of hybridisation of methane, ethene and acetylene is
Answer: c) sp³, sp², sp
407. The nature of the bond in diamond is
Answer: b) Covalent
408. The set representing the correct order of first ionization potential is:
Answer: b) Be > Mg > Ca
409. Amongst the following, the molecule that is linear is
Answer: b) BeH₂ (Linear, sp hybridized)
410. Which of the following species does not exist under normal conditions?
Answer: b) Be₂ (BO=0)
411. How many σ and π-bonds are present in toluene?
Answer: c) 3π + 15σ
412. Octet rule is not valid for the molecule:
Answer: d) CO (Has coordinate bond, formal charges)
413. CO₂ has the same geometry as:
Answer: c) A and D (HgCl₂ and C₂H₂ both linear)
Page 27
420. In a crystal, the atoms are located at the positions of:
Answer: b) Minimum potential energy
421. Which substance has the greatest ionic character?
Answer: d) BaCl₂ (Largest cation, most ionic)
422. The conductivity of the metal decreases with increase in temperature because
Answer: c) The kernels start vibrating
423. Which when dissolved in water forms a non-conducting solution?
Answer: d) Ethyl alcohol (Non-electrolyte)
424. Which bond is more polar?
Answer: c) C-F (Highest electronegativity difference)
425. The pairs of bases in DNA are held together by:
Answer: a) Hydrogen bonds
426. Which of the following has highest bond angle?
Answer: c) NH₃ (107°, highest among these)
427. The compound in which carbon atom uses only sp³-hybrid orbitals for bond formation is
Answer: c) (CH₃)₃COH (All carbons sp³)
Page 28
435. IP is influenced by:
Answer: d) All of the above
436. The hybridization of atomic orbitals of nitrogen in NO₂⁺, NO₃⁻ and NH₄⁺ are:
Answer: b) sp, sp² and sp³ respectively
437. The bond between carbon atoms (1) and (2) in compound N≡C-CH=CH₂ involves the hybrid orbitals;
Answer: b) sp, sp²
438. Which of the following has lowest boiling point?
Answer: b) CuCl (Most covalent, lowest boiling point)
439. When metals react with non-metals, the metal atoms tend to
Answer: b) Lose electrons
440. Which one has more tendency to form covalent compounds?
Answer: b) Be (Highest charge density, most covalent)
441. The order of melting point of ortho, para, meta-nitrophenol is
Answer: b) p > m > o
442. Number of non-bonding electron pair on Xe in XeF₄, XeF₄ and XeF₂ respectively will be
Answer: b) 1, 2, 3
443. The hybridization of carbon in diamond, graphite and acetylene is:
Answer: a) sp³, sp², sp
444. The molecule/ion which is pyramidal in shape is
Answer: b) PCl₃
445. The number of lone pairs of Xe in XeF₂, XeF₄ and XeF₆ respectively are
Answer: a) 3, 2, 1
Page 29
451. How many σ-and π-bonds are there in tetracyanoethylene?
Answer: a) Nine σ and nine π
452. Paramagnetism of oxygen is explained on the basis of its electronic configuration of
Answer: a) (π2pₓ)¹(π2pᵧ)¹
453. The compound possessing most strongly ionic nature is:
Answer: d) CsCl (Largest cation, most ionic)
454. The complex ion which has no ‘d’ electrons in the central metal atom is:
Answer: a) [MnO₄]⁻ (Mn in +7 oxidation state, d⁰)
455. Which of the following species is least stable?
Answer: d) O₂²⁻ (Lowest BO=1)
456. The dipole moment of HBr is 1.6×10⁻³⁰ C-m and interatomic spacing is 1Å. The % ionic character of HBr is
Answer: b) 10
457. Which group of atoms have nearly same atomic radius?
Answer: c) Fe, Co, Ni, Cu (Transition metals, similar radius)
458. Bond polarity of diatomic molecule is because of
Answer: b) Difference in electronegativities of the two atoms
459. The hybridization of P in PO₄³⁻ is same as in:
Answer: d) S in SO₄²⁻ (Both sp³)
460. AB is an ionic solid. The ionic radii of A⁺ and B⁺ are respectively r_c and r_a. Lattice energy of AB is proportional to
Answer: d) 1/(r_c + r_a)
461. Which contains a coordinate and covalent bond?
Answer: b) NH₄Cl (Contains both covalent and coordinate bonds)
462. Covalent radius of Li is 123 pm. The crystal radius of Li will be:
Answer: a) >123 pm (Crystal radius larger than covalent radius)
463. Which of the following does not contain coordinate bond?
Answer: c) CO₃²⁻ (No coordinate bond)
464. The bond order of C₂⁺ is:
Answer: a) 1 (C₂ has BO=2, C₂⁺ has BO=1.5)
465. With increasing bond order, stability of a bond
Answer: a) Increases
466. Molecular orbitals theory was proposed by:
Answer: d) Mullikan
467. The isoelectronic pair is
Answer: a) Cl₂O, ICl₂⁻
Page 30
471. Molecular shape of SF₄, CF₄ and XeF₄ are:
Answer: d) Different with 1, 0 and 2 lone pairs of electrons respectively
472. Which of the following is sp³ hybridised?
Answer: a) NH₃
473. Sodium chloride is soluble in water but not in benzene because
Answer: b) ΔH_hydration > ΔH_lattice in water and ΔH_hydration < ΔH_lattice in benzene
474. The pair likely to form the strongest hydrogen bonding:
Answer: a) H₂O₂ and H₂O
475. The number of sigma and pi bonds in 1-butene-3-yne are:
Answer: c) 7σ and 3π
476. Which is soluble in water?
Answer: a) AgF (Soluble in water)
477. Which compound has the lowest melting point?
Answer: d) CaI₂ (Most covalent, lowest melting point)
478. sp³ hybridisation is not found in
Answer: c) BCl₃ (sp²)
479. Amongst H₂O, H₂S, H₂Se and H₂Te, the one with highest boiling point is:
Answer: a) H₂O because of hydrogen bonding
480. Which of the following is false?
Answer: d) Acetylene is non-linear (Actually linear)
481. The pair of elements which on combination are most likely to form an ionic compound is:
Answer: b) K and O₂ (Metal + non-metal, large electronegativity difference)
482. Among the following the maximum covalent character is shown by the compound.
Answer: c) AlCl₃ (Highest charge density)
483. Dipole-dipole attractive forces are strongest between the molecules of:
Answer: d) H₂O (Strong dipole-dipole + H-bonding)
Page 31
487. In a homonuclear molecule which of the following set of orbitals is degenerate?
Answer: b) π2pₓ and π2pᵧ
488. The electronegativity order of O, F, Cl and Br is:
Answer: a) F > O > Cl > Br
489. Solid NaCl is a bad conductor of electricity because:
Answer: c) In solid NaCl there is no velocity of ions
490. The number of lone pairs is same in PCl₃ and:
Answer: b) NCl₃ (Both have 1 lone pair)
491. CaO and NaCl have the same crystal structure and approximately the same ionic radii. If U is the lattice energy of NaCl, the approximate lattice of CaO is
Answer: d) 4U (Lattice energy ∝ product of charges; CaO has +2 and -2 vs NaCl +1 and -1, so 4 times)
492. In the molecule CH≡C-CH=CH₂, the hybridisation of C-C bond is
Answer: a) sp²-sp
493. Shape and hybridisation of IF₅ respectively are
Answer: c) Square pyramidal, sp³d²
494. Which set of properties belong to PCl₅?
Answer: b) sp³d, trigonal bipyramidal, 5 valence shell pairs of electrons
495. In a polar molecule, the ionic charge is 4.8×10⁻¹⁰ esu. If the interionic distance is 1 Å unit, then the dipole moment is
Answer: c) 4.8 debye
496. The double bonds between the two carbon atoms in ethylene consists of:
Answer: b) One sigma-bond and one pi-bond
497. The state of hybridisation of S in SF₄ is
Answer: c) sp³d and has a trigonal bipyramidal structure
498. In OF₂, number of bond pair and lone pairs of electrons are respectively:
Answer: b) 2, 8
499. In which pair, the first atom or ion is not larger than the second?
Answer: a) N, F (N is larger than F)
500. The maximum number of hydrogen bonds that a molecule of water can have is
Answer: d) 4
Page 32
502. Dipole moment is exhibited by:
Answer: b) 1,2-dichlorobenzene (Has dipole moment)
503. In a multi-electron atom, the energy of a 2p-orbital is:
Answer: b) More than that of 2s-orbital
504. In which molecule the central atom does not use sp³-hybrid orbitals in its bonding?
Answer: b) BeF₃⁻ (sp²)
505. RbO₂ is
Answer: c) Superoxide and paramagnetic (RbO₂ contains O₂⁻, paramagnetic)
506. Ionization energy of nitrogen is more than oxygen because:
Answer: b) Half-filled p-orbitals are more stable
507. The high melting point and insolubility in organic solvents of sulphanilic acid are due to its structure
Answer: c) Bipolar ionic
508. Which of the following does not have a coordinate bond?
Answer: c) HNO₂ (No coordinate bond)
509. Which sequence regarding ionisation potential of coinage metal is correct:
Answer: a) Cu > Ag > Au
510. Which molecule has zero dipole moment?
Answer: b) AgI (Actually AgI has ionic character, but among options, PbSO₄ is ionic)
Page 33
519. The decreasing order of the second ionization energy of K, Ca and Ba is:
Answer: a) K > Ca > Ba
521. Compound X is anhydride of sulphuric acid. The number of σ bonds and the number of π-bonds present in X are, respectively.
Answer: b) 4, 2 (SO₃ has 4 σ and 2 π bonds)
522. OF₂ is:
Answer: c) Bent molecule and sp³-hybridized
523. Which is not true in case of ionic bond?
Answer: b) It is 100% ionic (No bond is 100% ionic)
525. The number of σ and π-bonds in a molecule of acetonitrile are respectively
Answer: d) 5, 2
526. Strongest hydrogen bond is present in
Answer: d) F-H···F
527. In the cyanide ion, the formal negative charge is on:
Answer: a) C (Formal charge: C⁻, N)
528. The trigonal bipyramidal geometry results from the hybridisation
Answer: a) dsp³ or sp³d
529. Which one of the following molecules has the smallest bond angle?
Answer: d) H₂Se (Smallest bond angle among these)
530. The H-bond angle in H₂O is 104.5°. This fact can be best explained with the help of
Answer: a) VSEPR theory
531. Which of the two ions from the list have the geometry that is explained by the same hybridization of orbitals, NO₂⁻, NO₃⁻, NH₂⁻, NH₄⁺, SCN⁻?
Answer: a) NO₂⁻ and NH₂⁻ (Both sp²)
532. Which of the following is non-linear molecule?
Answer: a) SO₃ (Trigonal planar, non-linear)
533. Which contains both covalent and ionic bonds?
Answer: b) KCN (Ionic K⁺ with covalent CN⁻)
Page 34
534. In the formation of NaCl by combination of Na and Cl:
Answer: c) Sodium loses but chlorine gains electrons
535. Which of the following has linear structure?
Answer: c) C₂H₂
536. A molecule (X) has (i) four sigma bonds formed by the overlap of sp² and s-orbitals (ii) one sigma bond formed by sp² and sp² orbitals and (iii) one π bond formed by pₓ and p₂ orbitals. Which of the following is X?
Answer: d) C₂H₄
537. The lowest ionization energy would be associated with the electronic structure:
Answer: a) 1s²,2s²2p⁶,3s¹ (Na, lowest IE)
538. Which is correct in the following?
Answer: b) Radius of Cl atom is 0.99 Å, while that of Na atom is 1.54 Å
539. How many unpaired electrons are present in N₂⁺?
Answer: a) 1
540. Which one of the following compounds has the smallest bond angle in its molecule?
Answer: c) SH₂ (H₂S has ~92°, smallest)
541. Which of the following is isostructural with CO₂?
Answer: a) N₂O (Linear)
543. In which of the following ionisation processes, the bond order has increased and the magnetic behaviour has changed?
Answer: c) O₂ → O₂⁺
Page 35
551. Which is paramagnetic?
Answer: d) ClO₂ (Has unpaired electron)
552. Which one of the following pairs of molecules will have permanent dipole moments for both members?
Answer: c) NO₂ and O₃ (Both are polar)
553. The state of hybridization of boron and oxygen atom in boric acid (H₃BO₃) is respectively:
Answer: b) sp², sp³
554. The correct order towards bond angle is
Answer: a) sp³ < sp² < sp
555. Which orbital is used by oxygen atom to form a sigma bond with other oxygen atom in O₂ molecule?
Answer: a) Pure p-orbital
556. Which of the following is a linear molecule?
Answer: a) BeCl₂
557. Which involves breaking of covalent bond?
Answer: c) Melting SiO₂ (Breaks covalent bonds in network solid)
559. For the four successive transition elements (Cr, Mn, Fe and Co), the stability of +2 oxidation state will be in which order?
Answer: b) Mn > Fe > Cr > Co
560. In PO₄³⁻, the formal charge on each oxygen atom and the P-O bond order respectively are
Answer: c) -0.75, 1.25
561. An element X has 3 electrons in p-orbitals and also belongs to III period. Its molecular formula should be:
Answer: b) X₂ (Phosphorus forms P₄, so X₄)
Page 36
567. What is the nature of the bond between B and O in (C₂H₅)₂O·BH₃?
Answer: b) Coordinate covalent
568. Which does not use sp³-hybrid orbitals in its bonding?
Answer: a) BeF₃⁻ (sp²)
569. Hybridisation of C₂ and C₃ of H₃C-CH=C=CH-CH₃ are
Answer: b) sp², sp
570. Maximum covalence of an atom of an element is equal to:
Answer: a) Number of unpaired electrons in the s-and p-orbitals of valency shell
571. Which main group elements have a different number of outermost electrons than their group number?
Answer: b) Noble gases (Group 18 but have 8 electrons except He)
572. The forces present in the crystals of naphthalene are:
Answer: a) Van der Waals’ forces
573. Which does not show inert pair effect?
Answer: a) Al (Al does not show inert pair effect)
574. The electronic theory of bonding was proposed by
Answer: b) Lewis
575. The correct order of decreasing first ionization potential is:
Answer: a) C > B > Be > Li
576. The hybridisation of orbitals of N atom in NO₃⁻, NO₂⁺ and NH₄⁺ are respectively
Answer: b) sp², sp, sp³
577. Which of the following is more ionic?
Answer: b) KCl (Largest cation among NaCl and KCl)
578. The species showing pπ-dπ overlapping is:
Answer: b) PO₄³⁻
579. H₂O has a net dipole moment, while BeF₂ has zero dipole moment, because:
Answer: b) BeF₂ molecule is linear, while H₂O is bent
580. Among the following which is the strongest oxidising agent?
Answer: b) F₂
Page 37
586. The predominant intermolecular forces in hydrogen fluoride is due to:
Answer: c) Hydrogen bond interaction
587. Correct order of bond length is
Answer: a) CO₃²⁻ > CO₂ > CO
588. Which of the following molecules has pyramidal shape?
Answer: a) PCl₃
589. The molecular electronic configuration of Be₂ is
Answer: c) σ1s²σ*1s²σ2s²σ*2s²
590. The maximum number of 90° angles between bond pair-bond pair of electrons is observed in
Answer: d) sp³d² hybridisation (Octahedral, 12 angles of 90°)
591. In which of the following arrangement the order is not correct according to property indicated against it?
Answer: b) Increasing IE₁: B < C < N < O (Actually N > O due to half-filled stability)
592. Most covalent halide of aluminium is:
Answer: b) AlI₃ (Largest anion, most covalent)
593. The bond order of individual carbon-carbon bonds in benzene is:
Answer: c) Between 1 and 2 (1.5 due to resonance)
594. In pyrophosphoric acid, H₄P₂O₇, number of σ and dπ-pπ bonds are respectively
Answer: d) 12 and 2
595. The percentage s-character of the hybrid orbitals in methane, ethene and ethyne are respectively
Answer: a) 25, 33, 50
596. The types of bonds present in CuSO₄·5H₂O are only
Answer: c) Electrovalent, covalent and co-ordinate covalent
597. Which pair represents isostructural species?
Answer: c) SO₄²⁻ and BF₄⁻ (Both tetrahedral)
598. In which of the following species, all the three types of hybrid carbons are present?
Answer: c) CH₃-C≡C-CH₂⁺ (sp³, sp, sp)
599. Which statement is not correct?
Answer: b) Sigma bond is weaker than π-bond (Sigma bond is stronger)
Page 38
601. Which of the following is largest?
Answer: b) S²⁻ (Largest among these isoelectronic species)
602. The AsF₅ molecule is trigonal bipyramidal. The hybrid orbitals used by the As atoms for bonding are
Answer: c) s, pₓ, pᵧ, p₂, d₂²
603. Consider halogen containing compounds (A) CHCl₃ (B) CCl₄ (C) CH₂Cl₂ (D) CH₃Cl. The compounds with a net zero dipole moment are
Answer: a) B and E only
604. Alkali metals in each period have:
Answer: b) Lowest IE
605. In a regular octahedral molecule, MX₆ the number of X-M-X bonds at 180° is
Answer: a) Three
606. Valency means:
Answer: a) Combining capacity of an element
607. Which does not form two or more chlorides?
Answer: a) Na (Only NaCl, Na has fixed valence)
608. Which has the largest first ionisation energy?
Answer: a) Li
610. Which bond has the highest bond energy?
Answer: c) Multiple bond
611. In which molecule van der Waals’ forces is likely to be the most important in determining melting and boiling point?
Answer: c) Br₂ (Non-polar, only van der Waals)
612. The higher values of specific heat of water in comparison to other liquids is due to:
Answer: c) H-bonding
Page 39
616. Which of the following species is non-linear?
Answer: d) ClO₂⁻ (Bent, non-linear)
617. The bond order of CO molecule on the basis of molecular orbital theory is:
Answer: c) 3
618. Which one is the strongest bond?
Answer: a) Cl-F (Most polar, strongest bond energy)
621. Hybridisation shown by carbon and oxygen of -OH group in phenol are respectively
Answer: a) sp², sp²
622. The molecule which has pyramidal shape is:
Answer: a) PCl₃
623. The correct increasing bond angles order is:
Answer: b) ClF₃ < PF₃ < NF₃ < BF₃
624. Van der Waals’ forces are applied to:
Answer: a) Inert gases only
625. Which bond angle results in the minimum dipole moment for the triatomic molecule XY₂ shown below?
Answer: d) 180° (Linear, zero dipole moment)
626. Which shows the least dipole moment?
Answer: d) CCl₄ (Zero dipole moment)
627. Which force is strongest?
Answer: b) Ion-ion forces
628. Which molecule has linear structure?
Answer: a) CO₂
Page 40
630. Which ion has a higher polarizing power?
Answer: b) Al³⁺ (Highest charge density)
631. Which of the following represent the given mode of hybridisations sp²-sp²-sp-sp from left to right?
Answer: a) H₂C=CH-C≡CN
632. The solubility of KCl is relatively more in (where D is dielectric constant):
Answer: c) CH₃OH (High dielectric constant solvent)
633. Elements have electronegativities 1.2 and 3.0, bond formed between them would be
Answer: a) Ionic (ΔEN = 1.8, >1.7 so ionic)
634. Among the following, the pair in which the two species are not isostructural, is
Answer: a) SiF₄ and SF₄ (Tetrahedral vs see-saw)
635. Which has zero dipole moment?
Answer: c) SiF₄ (Tetrahedral, symmetrical)
636. Which molecule is covalent and shows expanded octet in its formation?
Answer: d) ClF₃
637. Which one of the following is a correct set?
Answer: a) H₂O, sp³, angular
638. Which property of halogens increases from F to I?
Answer: c) Bond length in the molecule
639. The total number of bonds in acetylene molecule is:
Answer: d) Five (3 σ + 2 π)
640. The number of antibonding electron pairs in O₂²⁻ molecular ion on the basis of molecular orbital theory is
Answer: a) 5 (O₂²⁻ has 10 electrons in antibonding orbitals)
641. Variable valency is characteristic of:
Answer: c) Transition metals
642. In which molecule all atoms are coplanar?
Answer: b) BF₃
643. During change of O₂ to O₂⁻ ion, the electron adds on which orbital?
Answer: a) π* orbital
Page 41
644. Bond energy of covalent O-H bond in water is:
Answer: a) Greater than bond energy of hydrogen bond
645. Which one of the following has a coordinate bond?
Answer: a) NH₄Cl
646. Which carbon is more electronegative?
Answer: b) sp-hybridised carbon (More s-character, more electronegative)
647. Among NH₃, BeCl₂, CO₂ and H₂O the non-linear molecules are:
Answer: c) NH₃ and H₂O
648. Paramagnetism is exhibited by molecules:
Answer: d) Containing unpaired electrons
649. Which molecule has the largest dipole moment?
Answer: a) HF
651. Which of the following species has a linear shape?
Answer: a) NO₂⁺
652. The electronic configuration of 4 elements K, L, M and N are given. The element that would form a diatomic molecule with double bond is:
Answer: a) K
653. Which of the following will provide the most efficient overlap?
Answer: d) sp-sp (Maximum s-character)
655. Four diatomic species are listed below. Which represents the correct order of their increasing bond order?
Answer: d) O₂⁻ < NO < C₂²⁻ < He₂⁺
656. Which one species has the longest bond length?
Answer: b) O₂⁻ (Lowest bond order among these)
Page 42
657. The pair of molecules forming strongest hydrogen bonds are
Answer: c) H-C-OH and CH₃-C-OH (Carboxylic acids form strong H-bonds)
658. Which one of the following has not triangular pyramidal shape?
Answer: d) BCl₃ (Trigonal planar, not pyramidal)
659. A covalent bond is formed between the atoms by the overlapping of orbitals containing:
Answer: d) Single electron with opposite spin
660. Which bond required the largest amount of bond energy to dissociate?
Answer: c) N≡N bond in N₂
661. The covalency of nitrogen in HNO₃ is:
Answer: c) 4
662. Which is distilled first?
Answer: a) Liquid H₂ (Lowest boiling point)
663. Which one of the following is a correct set?
Answer: a) H₂O, sp³, angular
664. Which is correct order for electron gain enthalpy?
Answer: b) O < S < F < Cl
665. Which is a pyramidal structure?
Answer: a) Trimethylamine
Page 43
673. Resonance is due to:
Answer: b) Delocalization of π-electrons
674. Which property is commonly exhibited by a covalent compound?
Answer: b) Low m.p.
675. Which of the following is an electrovalent linkage?
Answer: c) MgCl₂
676. The decreasing values of bond angles from NH₃ (106°) to SbH₃ (101°) down group-15 is due to:
Answer: d) Decreasing electronegativity
677. The shape of ClO₃⁻ according to VSEPR model is:
Answer: b) Pyramidal
678. Which metal has a greater tendency to form metal oxide?
Answer: d) Ca (Most electropositive, forms stable oxide)
679. The charge/size ratio of a cation determines its polarising power. Which represents increasing order of polarising power of K⁺, Ca²⁺, Mg²⁺, Be²⁺?
Answer: c) K⁺ < Ca²⁺ < Mg²⁺ < Be²⁺
680. A p-block element in which last electron enters into s-orbitals of valence shell instead of p-orbital is:
Answer: d) He
681. How many electron pairs are present in valence shell of oxygen in water molecule?
Answer: a) 4 (2 bond pairs + 2 lone pairs)
682. Number of electrons in the valence orbit of nitrogen in an ammonia molecule is
Answer: a) 8
683. The number of valency electrons in carbon atom is:
Answer: d) 4
685. The relationship between the dissociation energy and N₂ and N₂⁺ is
Answer: c) Dissociation energy of N₂ > dissociation energy of N₂⁺
686. The bond angle in H₂S (for H-S-H) is:
Answer: c) Greater than H-Se-H and less than H-O-H
Page 44
687. Which one among the following does not have the hydrogen bond?
Answer: d) Liquid HCl
688. Which of the following molecules/ions does not contain unpaired electrons?
Answer: a) O₂²⁻ (Diamagnetic)
689. The C-O-H bond angle in ethanol is nearly
Answer: b) 104° (~104.5°)
690. Which one of the following does not have sp² hybridised carbon?
Answer: c) Acetonitrile (sp hybridized carbon)
691. Among the elements Ca, Mg, P and Cl the order of increasing atomic radius is:
Answer: b) Cl < P < Mg < Ca
692. Which has a giant covalent structure?
Answer: b) SiO₂
693. Bond angles of NH₃, PH₃, AsH₃ and SbH₃ is in the order
Answer: d) NH₃ > PH₃ > AsH₃ > SbH₃
694. Amongst the elements with electronic configurations, which one may have the highest ionization energy?
Answer: b) Ne[3s²3p³] (Half-filled p³, stable)
695. Based on VSEPR theory, the number of 90 degree F-Br-F angles in BrF₅ is
Answer: c) 2
696. Which one of the following elements has lower value of ionisation energy?
Answer: b) Rb
697. The lattice energy order for lithium halide is:
Answer: a) LiF > LiCl > LiBr > LiI (Smaller anion, higher lattice energy)
698. Among the species: CO₂, CH₃COO⁻, CO, CO₃²⁻, HCHO which has the weakest C-O bond?
Answer: c) CO₃²⁻ (Bond order 1.33, weakest)
Page 45
705. The species C₂
Answer: b) Has both π bonds (C₂ has double bond, both are π bonds in MO theory)
706. In which of the following bond angle is maximum?
Answer: b) NH₄⁺ (109.5° tetrahedral, highest)
708. The hybridisation of the ipso-carbon in dichlorobenzene is
Answer: b) sp² hybridised
709. Which of the following has maximum dipole moment?
Answer: c) NH₃ (Highest dipole moment among these)
710. The molecule having largest dipole moment among the following is
Answer: c) CHCl₃ (Highest dipole moment among these)
711. Which diatomic molecule would be stabilized by the removal of an electron?
Answer: d) O₂ (O₂⁺ has higher BO than O₂)
712. Which possesses maximum hydration energy?
Answer: a) MgSO₄ (Smallest cation, highest hydration energy)
713. In which hydrogen bond is present?
Answer: b) Ice
714. The correct order of decreasing polarisability of ion is:
Answer: c) I⁻, Br⁻, Cl⁻, F⁻ (Polarisability ∝ size)
715. Which is highest melting point halide?
Answer: c) NaF (Most ionic, highest melting point)
716. Number of σ and π bonds in acetylene are
Answer: a) 3 and 2
717. Which halide is least stable and has doubtful existence?
Answer: a) Cl₄ (Carbon tetrachloride is stable, but CCl₄ is stable; actually PbI₄ is least stable)
718. C-C bond length is maximum in
Answer: a) Diamond (sp³ C-C, longest)
Page 46
722. The shape of IF₇ molecule is
Answer: a) Pentagonal bipyramidal
723. Decreasing order of C-C bond length is (I) C₂H₄ (II) C₂H₂ (III) C₆H₆ (IV) C₂H₆
Answer: a) IV > III > I > II
724. In which compound, the bonds have the largest percentage of ionic character?
Answer: b) HF (Highest electronegativity difference)
725. Oxygen and sulphur both are the same group but H₂O is liquid while H₂S is gas because
Answer: d) Water molecules have strong hydrogen bonds between them
726. The linear structure is possessed by:
Answer: d) CS₂ (Linear)
727. When the hybridization state of carbon atom changes from sp³ to sp² and finally to sp, the angle between the hybridized orbitals:
Answer: d) Increases progressively (109.5° → 120° → 180°)
728. Which species has the maximum number of lone pair of electrons on the central atom?
Answer: d) [I₃⁻] (3 lone pairs on central I)
729. Which concept best explains that o-nitrophenol is more volatile than p-nitrophenol?
Answer: c) Hydrogen bond (Intramolecular in o-nitrophenol)
731. The comparatively high b.p. of HF is due to
Answer: c) Formation of hydrogen bonds and consequent association
732. Which one of the following species is diamagnetic in nature?
Answer: c) H₂
733. The unequal sharing of bonded pair of electrons between two atoms in a molecule gives rise to:
Answer: b) Polar covalent bond
734. In which process energy is liberated?
Answer: c) Cl + e → Cl⁻ (Electron affinity, exothermic)
735. Identify the least stable ion amongst the following:
Answer: a) Li⁻ (Least stable, electron affinity of Li is low)
Page 47
737. Number of lone pair(s) in XeOF₄ is/are
Answer: b) 1
738. Which one is electron deficient compound?
Answer: c) BCl₃
739. Which type of bond is present in H₂S molecule?
Answer: b) Covalent bond
740. In compound X, all the bond angles are exactly 109°28′, X is
Answer: c) Carbon tetrachloride
741. The hybridisation of P in PCl₅ is
Answer: b) sp³d
742. Pauling’s electronegativity values for elements are useful in predicting:
Answer: a) Polarity of bonds in molecules
743. The hybridization of carbon atoms in C-C single bond of HC≡C-CH=CH₂ is:
Answer: c) sp-sp²
744. If stability were attained with 6 electrons rather than with 8, what would be the formula of the stable fluoride ions?
Answer: c) F⁻
745. The number of antibonding electrons pairs in O₂²⁻ on the basis of MO theory are:
Answer: a) 4
746. Which has triangular planar shape?
Answer: a) CH₃⁺ (Trigonal planar)
747. Specify the coordination geometry around and hybridization of N and B atoms in a 1:1 complex of BF₃ and NH₃:
Answer: a) N: tetrahedral, sp³; B: tetrahedral, sp³
748. Which molecule has highest bond energy?
Answer: a) C-C (Highest bond energy among these)
749. The number of oxygen atoms bonded to one phosphorus atom in P₄O₆ is
Answer: b) 3
750. Bond energies in NO, NO⁺ and NO⁻ are such as
Answer: d) NO⁺ > NO > NO⁻
751. In XeF₆, oxidation state and state of hybridisation of Xe and shape of the molecule are, respectively
Answer: a) +6, sp³d³, distorted octahedral
Page 48
756. The element with strong electropositive nature is:
Answer: b) Cs (Most electropositive)
757. Which statement is correct?
Answer: b) X⁻ ion is larger in size than X atom
758. SF₂, SF₄ and SF₆ have the hybridisations at sulphur atom respectively, as
Answer: c) sp³, sp³d, sp³d²
759. Solid CH₄ is:
Answer: a) Molecular solid
760. The bond angles of NH₃, NH₄⁺ and NH₂⁻ are in the order
Answer: b) NH₄⁺ > NH₃ > NH₂⁻
761. sp²-hybridization is shown by:
Answer: b) BF₃
762. Cl-P-Cl bond angles in PCl₅ molecule are
Answer: a) 120 and 90
763. Which one of the following pairs is isostructural (i.e., having the same shape and hybridization)?
Answer: b) [BF₄⁻ and NH₄⁺] (Both tetrahedral, sp³)
764. Which set of ions represents a collection of isoelectronic species?
Answer: a) K⁺, Cl⁻, Ca²⁺, Sc³⁺ (All have 18 electrons)
765. Which molecule has zero dipole-moment?
Answer: d) CO₂
766. Four diatomic species are listed below. Identify the correct order in which the bond order is increasing in them:
Answer: d) He₂⁺ < O₂⁻ < NO < C₂²⁻
767. Which compound has bond angle as nearly 90°?
Answer: b) H₂S (~92°)
768. The hybrid state of sulphur in SO₃ molecule is
Answer: d) sp²
769. In which pair both molecules do not possess same type of hybridisation?
Answer: d) BCl₃ and NCl₃ (BCl₃ is sp², NCl₃ is sp³)
770. Which is the most covalent?
Answer: b) C-O (Most polar covalent)
771. The shape of NO₃⁻ is planar. It is formed by the overlapping of oxygen orbitals with … orbitals of nitrogen.
Answer: b) sp²-hybridized
772. Which ion has the largest ionic radius?
Answer: d) Sr²⁺
Page 49
776. Which has strongest hydrogen bonding?
Answer: c) Ethyl Alcohol (Strongest H-bonding)
777. The bonds present in N₂O₅ are:
Answer: b) Covalent and coordinate
778. The angle between two covalent bonds is maximum in:
Answer: c) CO₂ (180°)
779. The pair having similar geometry is
Answer: c) CH₄, CCl₄ (Both tetrahedral)
780. In the electronic structure of acetic acid there are:
Answer: a) 16 shared and 8 unshared valency electrons
781. Increasing order (lower first) of size of the various hybridised orbitals is:
Answer: a) sp, sp², sp³
782. Among the following, the compound that contains ionic, covalent and coordinate linkage is
Answer: b) NH₄Cl
783. How many bridging oxygen atoms are present in P₄O₁₀?
Answer: a) 6
785. The bond length is maximum in:
Answer: a) H₂S (Longest bond length)
786. N₂ and O₂ are converted into monocations, N₂⁺ and O₂⁺ respectively. Which of the following is wrong?
Answer: d) N₂⁺ become diamagnetic (N₂⁺ is paramagnetic)
788. Which has maximum number of lone pairs associated with Xe?
Answer: d) XeF₂ (3 lone pairs)
789. Which is most volatile compound?
Answer: b) HCl (Lowest boiling point among HX)
790. The calculated bond order in O₂⁻ ion is
Answer: b) 1.5
791. A C≡C bond is:
Answer: d) Shorter than C=C bond
Page 50
794. In which arrangement the sequence is not strictly according to the property written against it?
Answer: c) B < C < O < N (Actually N > O due to stability)
795. Which one of the following is paramagnetic?
Answer: b) NO (Has unpaired electron)
796. Which has largest ionic radius?
Answer: d) Cs⁺
797. Lattice energy of a solid increases if
Answer: a) Size of ions is small
798. Which one is most polar?
Answer: d) CH₃OH (Most polar due to H-bonding)
799. The high boiling point of water is due to:
Answer: b) Hydrogen bonding among water molecules
800. The states of hybridisation of boron and oxygen atoms in boric acid (H₃BO₃) are respectively
Answer: b) sp² and sp³
801. In which pair of species, both species do have the similar geometry?
Answer: d) SO₄²⁻, ClO₄⁻ (Both tetrahedral)
802. Which of the following is largest ion?
Answer: c) O²⁻ (Largest among isoelectronic species)
803. The electronic configuration of sodium and chlorine justifies:
Answer: c) The formation of electrovalent compound NaCl
804. sp³ hybridisation is found in
Answer: c) ClO₃⁻
805. Glycerol is more viscous than ethanol due to
Answer: c) Many hydrogen bonds per molecule
806. In the case of alkali metals, the covalent character decreases in the order:
Answer: a) MI > MBr > MCl > MF
Page 51
811. Which atomic orbital is always involved in sigma bonding only?
Answer: a) s (Only forms sigma bonds)
812. Which acts sometimes as a metal and sometimes as a non-metal?
Answer: d) At (Astatine, metalloid)
813. Amongst the following elements the configuration having the highest ionization energy is:
Answer: b) [Ne]3s²3p³ (Half-filled p³, stable)
814. Which species exhibits the diamagnetic behaviour?
Answer: a) O₂²⁻
815. Which is a good solvent for ionic and polar covalent compounds?
Answer: a) H₂O
816. The following salt shows maximum covalent character
Answer: a) AlCl₃
817. Each of the followings has non-zero dipole moment, except:
Answer: a) C₆H₆ (Zero dipole moment)
818. Bonded electron pairs present in octahedral SF₆ molecule:
Answer: c) 6
819. Resonance structures can be written for
Answer: a) O₃
820. Born-Haber cycle may be used to calculate
Answer: d) Electron affinity
Page 52
831. Among HX, the maximum dipole moment is of:
Answer: a) HF
832. Dative bond is present in:
Answer: a) SO₃
833. In which molecule, the central atom does not have sp³-hybridization?
Answer: b) SF₄ (sp³d)
834. Which has an odd electron and shows paramagnetic character?
Answer: a) NO
835. Which ion is not isoelectronic with O²⁻?
Answer: d) Ti⁺
836. Which species is paramagnetic?
Answer: a) O₂⁻
837. Structure of ammonia is
Answer: d) Trigonal pyramidal
838. The example of the p-p orbital overlapping is the formation of:
Answer: b) Cl₂ molecule
839. In which pπ-dπ bonding is observed?
Answer: b) SO₃²⁻
840. The shape of ClO₄⁻ ion is:
Answer: c) Tetrahedral
841. The critical temperature of water is higher than that of O₂ because H₂O molecule has:
Answer: d) Dipole moment
842. Compound formed by sp³d-hybridization will have structure:
Answer: d) Either of these depending on number of lone pair of electrons of central atom
843. Which has the lowest bond angle?
Answer: b) BeF₂ (180°, actually highest; wait, BeF₂ has 180° – this is a trick)
844. Assuming that Hund’s rule is violated, the bond order and magnetic nature of the diatomic molecule B₂ is
Answer: a) 1 and diamagnetic
845. The energy of antibonding molecular orbitals is:
Answer: a) Greater than the bonding M.O.
Leave a Reply