Assertion (A) Decomposition of `H_(2)O_(2)` is a disproportionation reaction.
Reason (R ) `H_(2)O_(2)` molecule simultaneously undergoes oxidation and reduction.

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 regarding the assertion and reason about the decomposition of hydrogen peroxide (H₂O₂), we will analyze both statements step by step.

### Step 1: Understand the Assertion
The assertion states that the decomposition of H₂O₂ is a disproportionation reaction.

**Disproportionation Reaction Definition**: A disproportionation reaction is a specific type of redox reaction in which a single substance is both oxidized and reduced, resulting in the formation of two different products.

### Step 2: Write the Decomposition Reaction of H₂O₂
The decomposition of hydrogen peroxide can be represented by the following chemical equation:

\[ 2 H_2O_2 \rightarrow 2 H_2O + O_2 \]

### Step 3: Determine the Oxidation States
Next, we need to analyze the oxidation states of the elements in the reaction:

- In H₂O₂, the oxidation state of oxygen is -1.
- In H₂O, the oxidation state of oxygen is -2.
- In O₂ (molecular oxygen), the oxidation state of oxygen is 0.

### Step 4: Identify Oxidation and Reduction
Now, we can identify which species is being oxidized and which is being reduced:

- **Reduction**: H₂O₂ (oxidation state of O changes from -1 to -2 in H₂O) - Here, the oxygen is reduced.
- **Oxidation**: H₂O₂ (oxidation state of O changes from -1 to 0 in O₂) - Here, the oxygen is oxidized.

### Step 5: Conclusion on Assertion
Since H₂O₂ is undergoing both oxidation and reduction during its decomposition, we conclude that the assertion is true: the decomposition of H₂O₂ is indeed a disproportionation reaction.

### Step 6: Understand the Reason
The reason states that the H₂O₂ molecule simultaneously undergoes oxidation and reduction.

### Step 7: Conclusion on Reason
This statement is also true, as we have shown that H₂O₂ is both oxidized and reduced in the reaction.

### Final Conclusion
Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is:

**Both assertion and reason are true, and reason is the correct explanation of assertion.**

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