Question

Tarnishing of silver is due to formation of

• A. Its sulphate layer
• B. Its nitrate layer
• C. Its sulphide layer
• D. Its chloride layer

Hint:

Tarnishing of silver is due to formation of black silver sulphide \((Ag_2S)\).

Answer 1

The Correct Option is C

Step 1: Silver articles slowly become black when exposed to air for a long time.

Step 2: This black coating is called tarnish.

Step 3: Air contains small amounts of sulphur compounds such as hydrogen sulphide.

Step 4: Silver reacts with sulphur compounds to form silver sulphide. \[ 2Ag+H_2S \rightarrow Ag_2S+H_2 \]

Step 5: The black layer formed is mainly silver sulphide. \[ \boxed{\text{Its sulphide layer}} \]