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Assertion: When a solution of Na(2)ZnO(2...

Assertion: When a solution of `Na_(2)ZnO_(2)` is acidified with dilute HCl and treated with `H_(2)S,` a precipitate of ZnS is formed.
Reason: `Na_(2)ZnO_(2)` is decomposed by HCl to give `Zn^(2+)` ions.

A

If assertion is true but the reason is false

B

If assertion is false but reason is true

C

If both assertion and reason are true and reason is the correct explanation of assertion

D

If oth assertion and reason are true but reason is not the correct explanation of assertion

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states: "When a solution of Na₂ZnO₂ is acidified with dilute HCl and treated with H₂S, a precipitate of ZnS is formed." - **Analysis**: Sodium zincate (Na₂ZnO₂) does not react with dilute HCl to produce Zn²⁺ ions that would subsequently precipitate as ZnS upon treatment with H₂S. Instead, sodium zincate requires concentrated HCl for effective reaction, leading to the formation of zinc hydroxide (Zn(OH)₂) and sodium chloride (NaCl). Therefore, the assertion is **false**. ### Step 2: Analyze the Reason The reason states: "Na₂ZnO₂ is decomposed by HCl to give Zn²⁺ ions." - **Analysis**: When Na₂ZnO₂ reacts with concentrated HCl, it does indeed produce Zn²⁺ ions. The reaction can be represented as: \[ \text{Na}_2\text{ZnO}_2 + 2\text{HCl} \rightarrow \text{Zn(OH)}_2 + 2\text{NaCl} \] Here, Zn(OH)₂ can further react with H₂S to form ZnS precipitate. Therefore, the reason is **true**. ### Conclusion Based on the analysis: - The assertion is **false**. - The reason is **true**. Thus, the correct answer is **Option B**: Assertion is false, but the reason is true. ---
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