Question

Answer the following questions relating your answers only to salts in the list given below:

Anhydrous calcium chloride, copper sulfate-$5$-water, sodium carbonate-$10$- water.

Which compound is (a) efflorescent?

Answer 1

Definition of Efflorescent:

• When substances are exposed to the atmosphere, then some of them lose their water of crystallization partially or completely to form a powder. Those substances are called Efflorescent.

Example:

• Copper sulfate$\mathrm{(}{\mathrm{CuSO}}_{\mathrm{4}}\mathrm{.}\mathrm{5}{\mathrm{H}}_{\mathrm{2}}\mathrm{O}\mathrm{)}$
• Sodium carbonate$\mathrm{(}{\mathrm{Na}}_{\mathrm{2}}{\mathrm{CO}}_{\mathrm{3}}\mathrm{.}\mathrm{10}\mathrm{}{\mathrm{H}}_{\mathrm{2}}\mathrm{O}\mathrm{)}$

The compounds which are Efflorescent are Copper sulfate $\mathrm{(}{\mathrm{CuSO}}_{\mathrm{4}}\mathrm{.}\mathrm{5}{\mathrm{H}}_{\mathrm{2}}\mathrm{O}\mathrm{)}$ and Sodium carbonate $\mathrm{(}{\mathrm{Na}}_{\mathrm{2}}{\mathrm{CO}}_{\mathrm{3}}\mathrm{.}\mathrm{10}\mathrm{}{\mathrm{H}}_{\mathrm{2}}\mathrm{O}\mathrm{)}$