A: Electrolysis of molten calcium hydride produces hydrogen gas at the cathode.
R: Hydrogen in calcium hydride is present as `H^(+)` ion.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements then mark (4)

Answer

To solve the given question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step 1: Analyze the Assertion (A)
The assertion states that "Electrolysis of molten calcium hydride produces hydrogen gas at the cathode."

- When calcium hydride (CaH₂) is melted and subjected to electrolysis, it dissociates into its constituent ions. The dissociation can be represented as:
\[ \text{CaH}_2 \rightarrow \text{Ca}^{2+} + 2\text{H}^{-} \]
- During electrolysis, the cathode is negatively charged, and it attracts the positively charged ions. In this case, the hydrogen ions (H⁻) will migrate towards the anode, where oxidation occurs, and hydrogen gas is produced.

### Step 2: Analyze the Reason (R)
The reason states that "Hydrogen in calcium hydride is present as H⁺ ion."

- In calcium hydride, hydrogen is actually present as H⁻ ions (hydride ions), not H⁺ ions. Therefore, the statement that hydrogen in calcium hydride is present as H⁺ ions is incorrect.

### Step 3: Conclusion
Since both the assertion (A) and the reason (R) are false, we can conclude that the correct answer is option D, which states that both the assertion and reason are false.

### Final Answer:
Both the assertion and reason are false.

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