Question

What is the formula of argentite?

Answer 1

1. Argentite is an ore of silver, it is a cubic silver sulphide i.e,${\mathrm{Ag}}_2\mathrm{S}$.
2. It only exist at temperature above ${179}^{\mathrm{o}}\mathrm{C}$.
3. It contains about $87\%$ silver.
4. It forms blackish-grey masses or coating with luster of metal and shinny black Streak.
5. The argentite crystal after cooling converted into monoclinic form from cubic without change in external appearance.
6. Silver is extracted from argentite with the help of sodium cyanide ($\mathrm{NaCN}$).