Assertion :- In the reaction
`Zn(s)+cu^(+2)(aq)rarrZn^(+2)(aq)+Cu(s)`
`Cu^(+2)` ions act as oxidising agent and Zn atoms act as a reducing agent.
Reason :- A substance when readily gain electrons from other, substance is an oxidising agent while reducing agent is a substance which can lose electrons to other susbtances.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are False.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states that in the reaction:
\[ \text{Zn(s)} + \text{Cu}^{2+}(aq) \rightarrow \text{Zn}^{2+}(aq) + \text{Cu(s)} \]
- Cu\(^{2+}\) ions act as the oxidizing agent.
- Zn atoms act as the reducing agent.

**Explanation**:
- In this reaction, zinc (Zn) is oxidized as it loses electrons to form Zn\(^{2+}\). The oxidation state of Zn changes from 0 to +2, indicating that it is losing electrons.
- Copper ions (Cu\(^{2+}\)) are reduced as they gain electrons to form solid copper (Cu). The oxidation state of Cu changes from +2 to 0, indicating that it is gaining electrons.

### Step 2: Analyze the Reason
The reason states:
- A substance that readily gains electrons from another substance is an oxidizing agent.
- A reducing agent is a substance that can lose electrons to other substances.

**Explanation**:
- The definition provided in the reason is accurate. An oxidizing agent is indeed a substance that gains electrons (is reduced) and a reducing agent is a substance that loses electrons (is oxidized).

### Step 3: Conclusion
Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the correct option is that both assertion and reason are true, and the reason is a correct explanation of the assertion.

### Final Answer:
**Both assertion and reason are true, and reason is a correct explanation of the assertion.**

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