When NaH is electrolysed, then _________ is released at anode.

Answer

To determine what is released at the anode when sodium hydride (NaH) is electrolyzed, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Electrolysis Process**: Electrolysis involves breaking down an ionic compound into its constituent elements using electricity. Sodium hydride (NaH) is an ionic compound.

2. **Identify the Components of NaH**: Sodium hydride consists of sodium ions (Na⁺) and hydride ions (H⁻).

3. **Determine the Products at the Electrodes**:
- **At the Cathode**: The cathode is where reduction occurs. In the case of NaH, sodium ions (Na⁺) gain electrons to form liquid sodium metal (Na). The half-reaction at the cathode is:
\[ 2 \text{Na}^+ + 2 \text{e}^- \rightarrow 2 \text{Na (l)} \]
- **At the Anode**: The anode is where oxidation occurs. The hydride ions (H⁻) lose electrons to form hydrogen gas (H₂). The half-reaction at the anode is:
\[ 2 \text{H}^- \rightarrow \text{H}_2 + 2 \text{e}^- \]

4. **Combine the Half-Reactions**: The overall reaction for the electrolysis of sodium hydride can be summarized as:
\[ 2 \text{NaH} \rightarrow 2 \text{Na (l)} + \text{H}_2 (g) \]

5. **Conclusion**: From the above analysis, we can conclude that hydrogen gas (H₂) is released at the anode during the electrolysis of sodium hydride.

### Final Answer:
When NaH is electrolyzed, then **hydrogen gas (H₂)** is released at the anode.

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