Question

7. Name the following compounds and also name the elements present in each of them. (You can ignore the numbers when naming these compounds.)

ix. $\mathrm{HgS}$

Answer 1

Part 1: Definition of compound:

A compound is defined as a pure substance that is made up of two or more elements in a fixed ratio by mass.

Part 2: Name of $\mathrm{HgS}$:

• Elements combine with sulfur to form sulfides.
• The name of $\mathrm{HgS}$ is Mercury sulfide.
• The elements present in $\mathrm{HgS}$ are mercury $\left(\mathrm{Hg}\right)$ and sulphur $\left(\mathrm{S}\right)$.

Hence, the name of $\mathrm{HgS}$ is Mercury sulphide.