Q. With reference to ‘Silver articles’, which of the following statements is/are correct?
1. Silver articles turn black after some time when exposed to air.
2. It happens due to coating of silver sulphide.
Select the correct answer from the code given below :
a) Only 2
b) Neither 1 nor 2
c) Both 1 and 2
d) Only 1
Correct Answer: c) Both 1 and 2
Question from UPPSC Prelims 2025
Explanation:
Statement 1 is correct: Silver articles tarnish and appear black when exposed to air over time.
Statement 2 is correct: The black tarnish is a thin film of silver sulphide (Ag2S) formed when silver reacts with trace sulfur-containing gases in air, especially hydrogen sulphide (H2S). This is the primary cause of blackening; silver oxide is not the main tarnish under normal conditions.
Therefore, both statements are correct.