Chemical Bonding and Molecular Structure
Previous year questions with solutions · 2000 – 2026
109 Questions
36 Papers covered
5.56% ↓16.7% Weightage in 2026
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Year-wise statistics questions · papers · average per paper · weightage Year Questions Papers Avg / paper Weightage 2026 5 2 2.5 5.56% ↓16.7% 2025 3 1 3 6.67% ↓3.8% 2024 7 2 3.5 6.93% ↑76.7% 2023 2 1 2 3.92% ↓1% 2022 4 2 2 3.96% ↓34% 2021 3 1 3 6.00% ↑35% 2020 2 1 2 4.44% ↑100% 2019 1 1 1 2.22% ↓50% 2018 2 1 2 4.44% ↓33.3% 2017 3 1 3 6.67% ↓14.3% 2016 7 2 3.5 7.78% →0% 2015 7 2 3.5 7.78% ↑75% 2014 2 1 2 4.44% ↓43.5% 2013 7 2 3.5 7.87% ↑4.9% 2012 6 2 3 7.50% ↓24.1% 2011 8 2 4 9.88% ↑31.7% 2010 6 2 3 7.50% ↓23.5% 2009 5 1 5 9.80% ↑66.7% 2008 3 1 3 5.88% ↑47.1% 2007 2 1 2 4.00% ↓60% 2006 5 1 5 10.00% ↑25% 2005 4 1 4 8.00% ↓4% 2004 4 1 4 8.33% ↑308.3% 2003 1 1 1 2.04% ↓49% 2002 2 1 2 4.00% ↓49% 2001 4 1 4 7.84% →0% 2000 4 1 4 7.84%
All 109 MCQ 100 Matching 8 Multiple Correct 1
TopicAll Bond Parameters: Bond Length, Bond Energy and Bond Angle Dipole Moment, Polarity and Non-Polar Molecules Fajans' Rule Formal Charge and Resonance Hybridisation Hydrogen Bonding and van der Waals Forces Lewis Structures, Octet Rule and Coordinate Bond Molecular Orbital Theory (MOT) VSEPR Theory and Molecular Geometry Valence Bond Theory (VBT) and Orbital Overlap π-Bonding, pπ–pπ and dπ–pπ Bonding YearAll 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000
⚠ 4 of these questions are out of the current syllabus (marked on the question).
61
In which of the following molecules the central atom does not have sp3 hybridization?
CH4 SF4 BF4- NH4+
AIPMT 2010 (Mains)
62
Some of the properties of the two species, NO3- and H3O+ are described below. Which one of them is correct?
Dissimilar in hybridization for the central atom with different structures. Isostructural with same hybridization for the central atom. Isostructural with different hybridization for the central atom. Similar in hybridization for the central atom with different structures.
AIPMT 2010 (Mains)
63
In which of the following pairs of molecules/ ions, the central atoms have sp2 hybridisation ?
NO2- and NH3 BF3 and NO2- NH2- and H2O BF3 and NH2-
AIPMT 2010 (Prelims)
64
Which one of the following species does not exist under normal conditions?
Be2+ Be2 B2 Li2
AIPMT 2010 (Prelims)
65
In which one of the following species the central atom has the type of hybridization which is not the same as that present in the other three ?
SF4 I3- SbCl52- PCl5
AIPMT 2010 (Prelims)
66
The correct order of increasing bond angles in the following species is
Cl2O < ClO2 < ClO2- ClO2 < Cl2O < ClO2- Cl2O < ClO2- < ClO2 ClO2- < Cl2O < ClO2
AIPMT 2010 (Prelims)
67
What is the dominant intermolecular force or bond that must be overcome in converting liquid CH3OH to a gas?
Dipole-dipole interaction Covalent bonds London dispersion force Hydrogen bonding
AIPMT 2009
68
According to MO theory which of the lists ranks the nitrogen species in terms of increasing bond order ?
N22- < N2- < N2 N2 < N22- < N2- N2- < N22- < N2 N2- < N2 < N22-
AIPMT 2009
69
In which of the following molecules/ions BF3, NO2-, NH2- and H2O, the central atom is sp2 hybridised?
NH2- and H2O NO2- and H2O BF3 and NO2- NO2- and NH2-
AIPMT 2009
70
The energy absorbed by each molecule (A2) of a substance is 4.4 10-19 J and bond energy per molecule is 4.0 10-19 J. The kinetic energy of the molecule per atom will be
2.2 10-19 J 2.0 10-19 J 4.0 10-20 J 2.0 10-20 J
Out of syllabus AIPMT 2009
71
In the case of alkali metals, the covalent character decreases in the order
MF > MCl > MBr > MI MF > MCl > MI > MBr MI > MBr > MCl > MF MCl > MI > MBr > MF
Out of syllabus AIPMT 2009
72
Four diatomic species are listed below. Identify the correct order in which the bond order is increasing in them
NO < O2- < C22- < He2+ O2- < NO < C22- < He2+ C22- < He2+ < O2- < NO He2+ < O2- < NO < C22-
AIPMT 2008
73
The correct order of increasing bond angles in the following triatomic species is
NO2+ < NO2 < NO2- NO2+ < NO2- < NO2 NO2- < NO2+ < NO2 NO2- < NO2 < NO2+
AIPMT 2008
74
The angular shape of ozone molecule (O3) consists of
1σ and 1π bond 2σ and 1π bond 1σ and 2π bonds 2σ and 2π bonds
AIPMT 2008
75
In which of the following pairs, the two species are isostructural?
SO32- and NO3- BF3 and NF3 BrO3- and XeO3 SF4 and XeF4
AIPMT 2007
76
The correct order of C-O bond length among CO, CO32-, CO2 is
CO < CO32- < CO2 CO32- < CO2 < CO CO < CO2 < CO32- CO2 < CO32- < CO
AIPMT 2007
77
Which of the following is not a correct statement?
Multiple bonds are always shorter than corresponding single bonds. The electron-deficient molecules can act as Lewis acids. The canonical structures have no real existence. Every AB5 molecule does in fact have square pyramid structure.
AIPMT 2006
78
Which of the following is not isostructural with SiCl4 ?
NH4+ SCl4 SO42- PO43-
AIPMT 2006
79
Which of the following species has a linear shape?
O3 NO2- SO2 NO2+
AIPMT 2006
80
The electronegativity difference between N and F is greater than that between N and H yet the dipole moment of NH3 (1.5 D) is larger than that of NF3 (0.2 D). This is because
in NH3 the atomic dipole and bond dipole are in the opposite directions whereas in NF3 these are in the same direction in NH3 as well as in NF3 the atomic dipole and bond dipole are in the same direction in NH3 the atomic dipole and bond dipole are in the same direction whereas in NF3 these are in opposite directions in NH3 as well as in NF3 the atomic dipole and bond dipole are in opposite directions.
AIPMT 2006
81
In which of the following molecules are all the bonds not equal?
NF3 ClF3 BF3 AlF3
AIPMT 2006
82
Which of the following molecules has trigonal planar geometry?
BF3 NH3 PCl3 IF3
AIPMT 2005
83
The correct order in which the O-O bond length increases in the following is
O2 < H2O2 < O3 O3 < H2O2 < O2 H2O2 < O2 < O3 O2 < O3 < H2O2
AIPMT 2005
84
The correct sequence of increasing covalent character is represented by
LiCl < NaCl < BeCl2 BeCl2 < LiCl < NaCl NaCl < LiCl < BeCl2 BeCl2 < NaCl < LiCl
AIPMT 2005
85
Which of the following would have a permanent dipole moment?
SiF4 SF4 XeF4 BF3
AIPMT 2005
86
Among the following, the pair in which the two species are not isostructural is
SiF4 and SF4 IO3- and XeO3 BH4- and NH4+ PF6- and SF6
AIPMT 2004
87
In a regular octahedral molecule, MX6, the number of X - M - X bonds at 180 is
three two six four
AIPMT 2004
88
H2O is dipolar, whereas BeF2 is not. It is because
the electronegativity of F is greater than that of O H2O involves hydrogen bonding whereas BeF2 is a discrete molecule H2O is linear and BeF2 is angular H2O is angular and BeF2 is linear.
AIPMT 2004
89
In BrF3 molecule, the lone pairs occupy equatorial positions to minimize
lone pair - bond pair repulsion only bond pair - bond pair repulsion only lone pair - lone pair repulsion and lone pair - bond pair repulsion lone pair - lone pair repulsion only.
AIPMT 2004
90
Which one of the following statements is not correct for sigma- and pi- bonds formed between two carbon atoms?
sigma-bond is stronger than a pi-bond. Bond energies of sigma- and pi-bonds are of the order of 264 kJ/mol and 347 kJ/mol, respectively Free rotation of atoms about a sigma-bond is allowed but not in case of a pi-bond. Sigma-bond determines the direction between carbon atoms but a pi-bond has no primary effect in this regard.
AIPMT 2003