Silver ornaments become black after some time when exposed to air because:

Correct option is B

The correct answer is (B) Silver reacts with sulphur in the air to form silver sulphide.

Explanation:
Silver tarnishes when it reacts with sulphur in the air, forming silver sulphide (Ag₂S), which causes the black discoloration on the surface.

Information Booster:

• Tarnishing Process: This is a chemical reaction where silver loses its shine due to exposure to sulphur compounds in the atmosphere.
• Chemical Reaction: 2Ag + H₂S → Ag₂S + H₂ (Silver reacts with hydrogen sulphide to form silver sulphide).
• Common Occurrence: Tarnishing happens more in areas with high pollution or high humidity due to increased sulphur compounds in the air.

Additional Information:

• Silver reacts with hydrogen to form silver hydride – Incorrect, as silver does not readily form a stable hydride.
• Silver reacts with carbon to form silver carbide – Incorrect, as silver does not form silver carbide naturally.
• Silver reacts with nitrogen to form silver nitride – Incorrect, as silver nitride is not formed under normal atmospheric conditions.