Question

Sand from water is separated by:

• A. Sieving
• B. Evaporation
• C. Filtration
• D. Sedimentation and Decantation.

Answer 1

The correct option is D

Sedimentation and Decantation.

Explanation for correct option:

Option D

• Insoluble substances that are heavier than liquid can be separated by sedimentation and decantation.

Sedimentation:

• The process of settling down of heavier insoluble particles at the bottom of a liquid is called sedimentation.
• The heavier insoluble particles that settle down at the bottom of the liquid are called sediments.

Decantation:

• The process of pouring out a clear liquid from a vessel without disturbing the sediment is called decantation.
• For example, a mixture of sand and water can be separated through sedimentation and decantation.

Therefore, option D is correct.

Explanation for incorrect option:

Option A

Sieving:

• The method of separating the components of a mixture that are of different sizes by using a sieve is called sieving.
• A sieve is a shallow vessel that has small holes at its bottom.
• The size of the holes in the sieve depends upon the size of the components to be separated.

Therefore, option A is incorrect.

Option B

Evaporation:

• Salt can be separated from its solution because the mixing of salt in water is a change that can be reversed by evaporation.
• Evaporation is the process of changing a liquid into its vapor state by the action of heat.
• The process of evaporation can be made faster by heating.
• The process of evaporation is used on a large scale to obtain common salt from seawater.
• Sea water is trapped in shallow ponds and allowed to evaporate in the sun.

Therefore, option B is incorrect.

Option C

Filtration:

• The process of separating insoluble substances from a liquid using filter paper is called filtration.
• A filter paper is a piece of special paper that has millions of tiny holes in it.

Therefore, option C is incorrect.