Which of the following is NOT true of silver (Ag)?

• A. Silver is less reactive than copper.
• B. Silver is highly reactive with oxygen at room temperature.
• C. Silver forms a black tarnish when exposed to sulfur compounds.
• D. Silver is an excellent conductor of electricity.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the reactivity of silver compared to copper. Silver is known to be less reactive than copper, meaning it does not easily undergo chemical reactions, especially oxidation, under normal conditions.
2. Step 2: Analyze the statement about silver's reaction with oxygen at room temperature. Silver does not react significantly with oxygen at room temperature, which is why it does not form an oxide layer like some other metals do. This makes the statement 'Silver is highly reactive with oxygen at room temperature' false.
3. Step 3: Consider the tarnishing of silver. Silver reacts with sulfur compounds in the air, such as hydrogen sulfide, to form silver sulfide, which appears as a black tarnish on its surface. This is a true characteristic of silver.
4. Step 4: Review silver's electrical conductivity. Silver is one of the best conductors of electricity among metals, which is why it is widely used in electrical applications. This statement is true.
5. Step 5: Summarize the findings: The only statement that is NOT true about silver is that it is highly reactive with oxygen at room temperature, as silver is relatively inert to oxygen under these conditions.