Chemistry

Chemical Bonding and Molecular Structure

1,277 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

Which of the following is an explosive?

  1. RDX

  2. DDT

  3. BHC

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

RDX (Research Department Explosive) is a powerful high explosive used in military and commercial applications. DDT and BHC are both pesticides/insecticides, not explosives. RDX's chemical properties and classification as an explosive material are well-established in chemistry and military science, making it the correct answer.

Multiple choice

Which of the following bonds is present in aqueous HCl?

  1. Electrovalent bond

  2. Double covalent bond

  3. Non-Polar covalent bond

  4. Polar covlent bond

  5. Coordinate bond
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Liquified HCl does not allow the electric current to pass through it, showing the non-Polar covalent bond nature of HCl.

Multiple choice

Which of the following types of bonds can be broken by mercaptoethanol?

  1. Ionic bonds

  2. Hydrogen bonds

  3. Disulphide bonds

  4. Hydrophobic interactions

  5. Covalent bonds
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

It is an electromagnetic attractive interaction of a hydrogen atom and an electronegative atom such as nitrogen, oxygen, fluorine that comes from another molecule or chemical group.

Multiple choice

Which of the following elements is/are present in CFC’s?

  1. Fluorine

  2. Chlorine

  3. Argon

  4. Both (1) and (2)

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

CFCs (Chlorofluorocarbons) contain carbon, fluorine, and chlorine atoms - all three elements. The name itself indicates this: Chloro-Fluoro-Carbons. Argon is not present in CFCs. The answer choice D (Both 1 and 2) refers to options A (Fluorine) and B (Chlorine), making it correct.

Multiple choice

Which of the following compounds belongs to aziridine?

  1. Chlorophenamine

  2. Impramine

  3. Chloprazine

  4. Ethylene imine

  5. Ethylamine
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because aziridine is a three-membraned heterocyclic compound and this compound is less basic than acyclic aliphatic amine.

Multiple choice

Li resembles Mg mainly due to similarity in sizes of their atoms and ions. The main points of similarity are:

i. Both LiOH and Mg(OH)2 are strong bases. ii. Carbonates of both, on heating, decompose to produce oxides and carbon dioxide. iii. Both react with nitrogen to give covalent nitrides. iv. Both Li and Mg form solid bicarbonates. v. LiCl and MgCl2 are soluble in ethanol. vi. The hydroxides, bicarbonates and fluorides of both Li and Mg are sparingly soluble in water.

  1. i, iii and iv

  2. i, iv and vi

  3. ii, iii and v

  4. ii, v and vi

  5. iv, v and vi
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Li resembles Mg mainly due to similarity in sizes of their atoms and ions. The main points of similarity are:

  1. Both Li and Mg are quite hard.
  2. Both LiOH and Mg(OH)2 are weak bases.
  3. Carbonates of both Li and Mg on heating decompose to produce oxides and carbon dioxide.
  4. Both Li and Mg react with nitrogen to give ionic nitrides.
  5. Nitrates of both Li and Mg decompose on heating to give oxides.
  6. Both Li and Mg do not form solid bicarbonates.
  7. Because of covalent character, LiCl and MgCl2 are soluble in ethanol.
  8. The hydroxides, bicarbonates and fluorides of both Li and Mg are sparingly soluble in water.
Multiple choice

Structure of ethylamine is ______

  1. Square

  2. Pyramidal

  3. Triangular

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ethylamine (CH3CH2NH2) has a pyramidal structure around the nitrogen atom due to sp3 hybridization with three bond pairs and one lone pair, similar to ammonia (NH3). Square planar geometry occurs in some d8 metal complexes. Triangular planar geometry occurs in sp2 hybridized molecules like boron trifluoride. Ethylamine's nitrogen is definitely not square or triangular planar.

Multiple choice

The molecule having the smallest bond angle is __________.

  1. AlCl3

  2. CH4

  3. H2O

  4. H2S

  5. XeF4
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

XeF4 has square planar geometry with bond angle 90o. It has the least bond angle among the given molecules. Increasing order of bond angle: XeF4 (90o) < H2S (92.3o) < H2O (104.5o) < CH4 (109.5o) < AlCl3 (120o)