Question

Which one of the following may be termed as a pure substance?

• A. Sodium chloride
• B. Soft drink
• C. Aerosol
• D. Soil

Answer 1

The correct option is A

Sodium chloride

The explanation for the correct answer:

Option (A) Sodium Chloride.

1. If all the constituent particles of a substance are the same in their chemical nature, it is called a pure substance.
2. Since sodium Chloride has a consistent chemical composition throughout, it can be regarded as a pure substance.
3. Sodium chloride is a compound having the formula NaCl.
4. It has definite melting and boiling point and cannot be separated down to simpler constituents through physical processes.

The explanation for the incorrect answer:

Option (B)-Soft drink

Option (C)-Aerosol

Option (D)-soil

1. If all the constituent particles of a substance are not the same in their chemical nature, it is called an impure substance.
2. Soil, soft drinks, and aerosols are impure substances and their compositions are not uniform.
3. They are considered as mixures.

Option (A) Sodium Chloride is a pure substance