Assertion (A): `F_(2)` undergoes disproportionation reaction.
Reason (R ): Fluorine shows both positive and negative oxidation states.

Options

A. If both `(A)` and `(R )` are correct and `(R )` is the correct explanation of `(A)`.
B. If both `(A)` and `(R )` are correct but `(R )` is not the correct explanation of `(A)`.
C. If `(A)` is correct but `(R )` is incorrect.
D. If both `(A)` and `(R )` are incorrect.

Explanation

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

### Step 1: Understand the Assertion
The assertion states that \( F_2 \) undergoes a disproportionation reaction. A disproportionation reaction is a specific type of redox reaction where a single species is simultaneously oxidized and reduced to form two different products.

### Step 2: Analyze Fluorine's Behavior
Fluorine, in its elemental form \( F_2 \), has an oxidation state of 0. In compounds, fluorine typically exhibits an oxidation state of -1 (for example, in \( HF \) or \( NaF \)). It does not exhibit a positive oxidation state because it is the most electronegative element, meaning it tends to gain electrons rather than lose them.

### Step 3: Determine if Disproportionation Occurs
For a disproportionation reaction to occur, a species must be able to both lose and gain electrons. Since fluorine only exists in the -1 oxidation state when it forms compounds and does not exhibit a positive oxidation state, it cannot undergo disproportionation. Therefore, the assertion that \( F_2 \) undergoes disproportionation is incorrect.

### Step 4: Understand the Reason
The reason provided states that fluorine shows both positive and negative oxidation states. However, as discussed, fluorine does not show a positive oxidation state. It only shows a -1 oxidation state in compounds. Therefore, the reason is also incorrect.

### Conclusion
Both the assertion and the reason are incorrect. Thus, the correct answer to the question is that both the assertion (A) and the reason (R) are false.

### Final Answer
Both Assertion (A) and Reason (R) are incorrect.

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