Question

Which substance would be expected to form a precipitate as a product of a chemical reaction?

a) Calcium sulfide
b) Silver hydroxide
c) Chromium (III) sulfate
d) Sodium phosphate

Answer 1

Silver hydroxide is expected to form a precipitate, as it is poorly soluble in water and tends to precipitate when formed during chemical reactions.

Step-by-step explanation:

Among the substances listed, the one expected to form a precipitate during a chemical reaction is b) Silver hydroxide. Silver hydroxide is poorly soluble in water, and when it is formed in an aqueous reaction, it tends to precipitate out of the solution.

For example, when solutions of silver nitrate (AgNO3) and sodium hydroxide (NaOH) are mixed, silver hydroxide precipitates out:
AgNO3(aq) + NaOH(aq) → AgOH(s) + NaNO3(aq)

To verify the presence of a precipitate like barium sulphate (BaSO4), as indicated in the Check Your Learning section, one could perform a qualitative test. The test involves adding a solution known to contain sulphate ions to a solution suspected of containing barium ions. If BaSO4 is present, a white precipitate will form.