Assertion : `[Co(NH_(3))_(5)Br]SO_(4)` gives white precipitate with barium chloride .
Reason : The complex `[Co(NH_(3))_(5)Br]SO_(4)` dissociates in the solution to give `Br^(-)` and `SO_(4)^(2-)`.

Options

A. If both Assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. if both assertion and reason are false

Explanation

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
The assertion states that the complex \([Co(NH_3)_5Br]SO_4\) gives a white precipitate with barium chloride (\(BaCl_2\)).

2. **Dissociation of the Complex**:
The complex \([Co(NH_3)_5Br]SO_4\) is a coordination compound. When it is dissolved in water, it dissociates into its constituent ions. The dissociation can be represented as:
\[ [Co(NH_3)_5Br]SO_4 \rightarrow [Co(NH_3)_5Br]^{2+} + SO_4^{2-} \]
Here, the complex ion \([Co(NH_3)_5Br]^{2+}\) carries a positive charge and the sulfate ion \(SO_4^{2-}\) carries a negative charge.

3. **Reaction with Barium Chloride**:
The sulfate ion \(SO_4^{2-}\) can react with barium chloride (\(BaCl_2\)). The reaction is:
\[ SO_4^{2-} + Ba^{2+} \rightarrow BaSO_4 \downarrow \]
Barium sulfate (\(BaSO_4\)) is known to be insoluble in water and forms a white precipitate.

4. **Conclusion on the Assertion**:
Since the sulfate ion from the dissociation of the complex reacts with barium ions to form a white precipitate of barium sulfate, the assertion is true.

5. **Understanding the Reason**:
The reason states that the complex dissociates to give \(Br^{-}\) and \(SO_4^{2-}\). However, from our dissociation equation, we see that the complex actually dissociates to give \([Co(NH_3)_5Br]^{2+}\) and \(SO_4^{2-}\), not \(Br^{-}\).

6. **Conclusion on the Reason**:
Therefore, the reason provided is false because it incorrectly states the products of the dissociation.

7. **Final Evaluation**:
Since the assertion is true and the reason is false, the correct conclusion is that the assertion is true but the reason is false.

### Final Answer:
The assertion is true, but the reason is false.