Question

A compound $\mathrm{X}$ consists of only molecules. Hence, $\mathrm{X}$ will have

• A. A crystalline hard structure
• B. A low melting and boiling point.
• C. An ionic bond
• D. A strong force of attraction between its molecules.

Answer 1

The correct option is B

A low melting and boiling point.

Part 1: The explanation for the correct answer:

Option B: A low melting and boiling point

1. Compound $\mathrm{X}$ has a molecule means it is formed with the atom of the same element.
2. So it will have a covalent bond. e.g. ${\mathrm{H}}_2,{\mathrm{Cl}}_2$ etc.
3. In a covalent bond because of weak intermolecular force, the boiling and melting point are low.

Part 2: The explanation for the incorrect option:

Option A: A crystalline hard structure.

In ionic compounds because of strong intermolecular force, it forms a hard crystalline solid. e.g. $\mathrm{NaCl}$

Option C: An ionic bond.

It is formed by two different atoms of which one is metal and the other is non-metal.

Option D: A strong force of attraction between its molecules

A strong force of attraction takes place in ionic compounds because of the presence of oppositely charged ions.

So, Option B is correct. The compound $\mathrm{X}$ will have a covalent bond.