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Statement-1: Zinc hydroxide dissolves in...

Statement-1: Zinc hydroxide dissolves in excess of `NaOH` solution to evolve dihydrogen gas.
Statement-2: Zinc hydroxide is amphoteric in nature.

A

Statement-1 is true, statement-2 is true, statement-2 is a correct explanation for statement-1

B

Statement-1 is true, statement-2 is true, statement-2 is not correct explanation for statement-1

C

Statement-1 is true, statement-2 is false

D

Statement-1 is false, statement-2 is true

Text Solution

AI Generated Solution

The correct Answer is:
To analyze the statements regarding zinc hydroxide, let's break down the information step by step. ### Step 1: Understanding Statement 1 **Statement 1:** Zinc hydroxide dissolves in excess of NaOH solution to evolve dihydrogen gas. - Zinc hydroxide (Zn(OH)₂) is known to be amphoteric, which means it can react with both acids and bases. - When zinc hydroxide is treated with excess sodium hydroxide (NaOH), it does not evolve dihydrogen gas. Instead, it forms a soluble complex, sodium zincate (Na₂ZnO₂), and water. **Conclusion for Statement 1:** This statement is **false** because zinc hydroxide does not evolve dihydrogen gas when it dissolves in NaOH. ### Step 2: Understanding Statement 2 **Statement 2:** Zinc hydroxide is amphoteric in nature. - As mentioned earlier, zinc hydroxide can react with both acids and bases. - When it reacts with acids, it behaves as a base, forming zinc ions (Zn²⁺) and water. - When it reacts with bases, it behaves as an acid, forming complex ions like Zn(OH)₄²⁻ or Na₂ZnO₂. **Conclusion for Statement 2:** This statement is **true** because zinc hydroxide exhibits amphoteric behavior. ### Final Conclusion - **Statement 1:** False - **Statement 2:** True Thus, the correct answer is that Statement 1 is false and Statement 2 is true. ---
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