Question

To separate a mixture of sand, common salt, camphor and iron fillings, Dhoni added water to the mixture in a test tube and shook it well. He found that one component dissolved in water. It was:

• A. Sand
• B. Iron fillings
• C. Camphor
• D. Common salt

Answer 1

The correct option is D

Common salt

The explanation for correct option:

(d) Common salt

When Dhoni added water to the mixture of sand, camphor, iron fillings and common salt he observed that salt got completely dissolved giving a homogenous mixture of salt and water.

The explanation for incorrect options:

(a) Sand

1. When water is added, sand will not dissolve in it, it will rather form a suspension.
2. A suspension is a heterogeneous mixture in which the particle of the solute settles down to the bottom of the tank if left untouched.

(b) Iron fillings

Iron fillings do not dissolve in water. They rather remain at the bottom of the tank.

(c) Camphor

1. Camphor does not dissolve in water it will give a colloidal solution.
2. A colloidal solution is a solution in which the size of the solute particles is intermediate to that of a true solution and suspension.

Hence, option (d) is the correct option.