Chemical Bonding and Molecular Structure
Previous year questions with solutions · 2000 – 2026
Year-wise statistics questions · papers · average per paper · weightage
| Year | Questions | Papers | Avg / paper | Weightage |
|---|---|---|---|---|
| 2026 | 5 | 2 | 2.5 | 5.56% ▼ 16.7% vs last year |
| 2025 | 3 | 1 | 3 | 6.67% ▼ 3.8% vs last year |
| 2024 | 7 | 2 | 3.5 | 6.93% ▲ 76.7% vs last year |
| 2023 | 2 | 1 | 2 | 3.92% ▼ 1% vs last year |
| 2022 | 4 | 2 | 2 | 3.96% ▼ 34% vs last year |
| 2021 | 3 | 1 | 3 | 6.00% ▲ 35% vs last year |
| 2020 | 2 | 1 | 2 | 4.44% ▲ 100% vs last year |
| 2019 | 1 | 1 | 1 | 2.22% ▼ 50% vs last year |
| 2018 | 2 | 1 | 2 | 4.44% ▼ 33.3% vs last year |
| 2017 | 3 | 1 | 3 | 6.67% ▼ 14.3% vs last year |
| 2016 | 7 | 2 | 3.5 | 7.78% same as last year |
| 2015 | 7 | 2 | 3.5 | 7.78% ▲ 75% vs last year |
| 2014 | 2 | 1 | 2 | 4.44% ▼ 43.5% vs last year |
| 2013 | 7 | 2 | 3.5 | 7.87% ▲ 4.9% vs last year |
| 2012 | 6 | 2 | 3 | 7.50% ▼ 24.1% vs last year |
| 2011 | 8 | 2 | 4 | 9.88% ▲ 31.7% vs last year |
| 2010 | 6 | 2 | 3 | 7.50% ▼ 23.5% vs last year |
| 2009 | 5 | 1 | 5 | 9.80% ▲ 66.7% vs last year |
| 2008 | 3 | 1 | 3 | 5.88% ▲ 47.1% vs last year |
| 2007 | 2 | 1 | 2 | 4.00% ▼ 60% vs last year |
| 2006 | 5 | 1 | 5 | 10.00% ▲ 25% vs last year |
| 2005 | 4 | 1 | 4 | 8.00% ▼ 4% vs last year |
| 2004 | 4 | 1 | 4 | 8.33% ▲ 308.3% vs last year |
| 2003 | 1 | 1 | 1 | 2.04% ▼ 49% vs last year |
| 2002 | 2 | 1 | 2 | 4.00% ▼ 49% vs last year |
| 2001 | 4 | 1 | 4 | 7.84% same as last year |
| 2000 | 4 | 1 | 4 | 7.84% |
⚠ 4 of these questions are out of the current syllabus (marked on the question).
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
The correct sequence of increasing covalent character is represented by
- LiCl < NaCl < BeCl2
- BeCl2 < LiCl < NaCl
- NaCl < LiCl < BeCl2
- BeCl2 < NaCl < LiCl
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
In a regular octahedral molecule, MX6, the number of X - M - X bonds at 180 is
- three
- two
- six
- four
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.
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.
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.
In NO3- ion number of bond pair and lone pair of electrons on nitrogen atom are
- 2, 2
- 3, 1
- 1, 3
- 4, 0
Main axis of a diatomic molecule is z, atomic orbitals px and py overlap to form which of the following orbitals.
- molecular orbital
- molecular orbital
- molecular orbital
- No bond will form
Which of the following two are isostructural?
- XeF2, IF2-
- NH3, BF3
- CO32-, SO32-
- PCl5, ICl5
In X-H Y, X and Y both are electronegative elements. Then
- electron density on X will increase and on H will decrease
- in both electron density will increase
- in both electron density will decrease
- on X electron density will decrease and on H will increase.