Tarnishing of ornaments is an example of ________.

Correct option is B

• Tarnishing of ornaments refers to the formation of a dull, discolored layer on metals, especially silver, due to a chemical reaction with the oxygen in the air. This process is an oxidation reaction, where the metal reacts with oxygen, moisture, or sulfur compounds, causing the metal to corrode or tarnish.
• For example, silver tarnishes when it reacts with hydrogen sulfide (H₂S) in the air, forming silver sulfide (Ag₂S).

•  Photolytic decomposition reaction involves the breaking down of a substance due to light, not related to tarnishing.
• Neutralisation reaction involves an acid reacting with a base to form salt and water, which is not relevant to tarnishing.
•  Exothermic reaction refers to a reaction that releases heat, but tarnishing is not specifically an exothermic process.

Thus, tarnishing of ornaments is best described as an oxidation reaction.