Paper 2 · June 2025 · Atomic Structure and Bonding

A mixture of sand and salt solution is to be separated so that the sand is left behind as a residue while the salt solution passes through. Name the separation method used.

Model answer

filtration

Also accepted: filtering

Explanation

Sand is insoluble in water, so it stays on the filter paper as the residue while the salt solution runs through it as the filtrate. Filtration is the method for separating an insoluble solid from a liquid.

Derived from ZIMSEC Chemistry 4024/2, June 2025, Q1(a)

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