Chemistry

Chemical Bonding and Molecular Structure

1,420 Questions

This section tests your knowledge of chemical bonding, molecular structure, and hybridization. It covers ionic and covalent bonds, octet rule exceptions, and molecular geometry. These chemistry questions are common in various competitive entrance examinations.

Ionic and covalent bondsHybridisation of elementsOctet rule exceptionsMolecular geometryIntermolecular forces

Chemical Bonding and Molecular Structure Questions

Multiple choice

An ionic bond A+ B– is most likely to be formed when

  1. the ionisation energy of A is high and the electron affinity of B is low

  2. the ionisation energy of A is low and the electron affinity of B is high

  3. the ionisation energy of A and the electron affinity of B is high

  4. the ionisation energy of A and the electron affinity of B is low
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An ionic bond A+ B– is most likely to be formed when the ionisation energy of A is low and the electron affinity of B is high.

Multiple choice

Which of the following have coordinate covalent bonds?

  1. Br2 and HCl

  2. Cl2 and F2

  3. NH4+ and H3O+

  4. FeCl3 and H2SO4
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hydronium ion contains 2 polar covalent bonds and 1 coordinate covalent bond. Ammonium ion contains 3 polar covalent bonds and 1 coordinate covalent bond.

Multiple choice

Which of the following statements is incorrect?

  1. KCl is soluble in water.

  2. HCl conducts electricity in its aqueous solution.

  3. Acetic acid is soluble in water.

  4. The bond formed between aluminum and fluorine is covalent.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The bond formed between aluminum and fluorine is ionic, because metals form ionic bonds with non-metals.

Multiple choice

Which of the following does not admit any division?

  1. Atom

  2. Molecules

  3. Compounds

  4. All of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

According to Dalton's atomic theory, the atom is the smallest indivisible unit of matter that cannot be divided further by chemical means. While modern physics has identified subatomic particles like protons and electrons, in the context of basic chemical units, the atom is considered the fundamental building block. Molecules and compounds are composed of multiple atoms and can be divided.

Multiple choice

What is the correct order of ion mobility of the following ions in an aqueous solution?

  1. Cation: H3O+ > Li+ > Na+, Anion: OH- > Br- > CH3COO-

  2. Cation: H3O+ > Na+ > Li+, Anion: OH- > Br- > CH3COO-

  3. Cation: Na+ > Li+ > H3O+, Anion: OH- > Br- > CH3COO-

  4. Cation: H3O+ > Li+ > Na+, Anion: CH3COO- > Br- > OH-

  5. Cation: H3O+ > Na+ > Li+, Anion: Br- > OH-> CH3COO-
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is the correct order of movement of anions and cations in an aqueous solution.

Multiple choice

Which of the statements is/are correct? A. Cr2+ ions are unstable in aqueous solution. B. Energy of 3d and 4s orbitals are the same for a hydrogen atom. C. Degenerate orbitals possess different energies.

  1. Only A

  2. Only B

  3. Only C

  4. Only A and B

  5. Only A and C
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cr2+ ions are unstable in aqueous solution, i.e highly reactive in aqueous solution. It is a correct statement. Energy of 3d and 4s orbitals are the same for a hydrogen atom.

Multiple choice

Match the Column – I (Calculated bond angles) with Column – II (Geometry) and select the correct option.

 
Column – I
Column – II
1. 90o A. Planar triangular (trigonal)
2. 72o B. Square antiprismatic
3. 99.6o C. Pentagonal bipyramidal
4. 120o D. Octahedral

  1. 1 - C, 2 - B, 3 - D, 4 - A

  2. 1 - D, 2 - B, 3 - C, 4 - A

  3. 1 - B, 2 - C, 3 - A, 4 - D

  4. 1 - D, 2 - C, 3 - B, 4 - A

  5. 1 - A, 2 - B, 3 - C, 4 - D
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Correct answer:

  1. 90o - D. Octahedral e.g: SF6
  2. 72o - C. Pentagonal bipyramidal e.g: IF7
  3. 99.6o - B. Square antiprismatic e.g: TaF83-
  4. 120o - A. Planar triangular (trigonal) e.g: SO3
Multiple choice

Which of the following iso-electronic species has the correct order of the size of ions?

  1. P-3 > S-2 > Cl- > Ar > K+ > Ca+2

  2. P-3 < S-2 < Cl- < Ar < K+ < Ca+2

  3. Ar > K+ > Ca+2> P-3 > S-2 > Cl-

  4. Ar > K+ > Ca+2 > P-3 > S-2 > Cl-

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Size of iso-electronic species ∝ 1/(Nuclear charge) This is quite clear from the following iso-electronic species, which contains a total of 18 electrons. Iso-electronic species with 18e- is arranged in the decreasing order of size is: P-3 > S-2 > Cl- > Ar > K+ > Ca+2.