The hydride ion `H^(-)` is a stronger base than its hydroxide ion `OH^(-)`. Which of the following reactions will occurs if sodium hydride (NaH) is dissolved in water ?

Options

A. `H^(-)+H_(2)Orarr` No rection
B. `H^(-)(aq)+H_(2)OrarrH_(2)O`
C. `H^(-)(aq)+ H_(2)O(l)rarrOH^(-)+H_(2)`
D. None of these

Answer

To solve the question regarding the reaction that occurs when sodium hydride (NaH) is dissolved in water, we can follow these steps:

### Step 1: Understand the Reactants
Sodium hydride (NaH) consists of sodium ions (Na⁺) and hydride ions (H⁻). The hydride ion is known to be a strong base.

### Step 2: Dissolution in Water
When NaH is added to water, it dissociates into its constituent ions:
\[ \text{NaH} \rightarrow \text{Na}^+ + \text{H}^- \]

### Step 3: Reaction of Hydride Ion with Water
The hydride ion (H⁻) will react with water (H₂O). The reaction can be represented as:
\[ \text{H}^- + \text{H}_2\text{O} \rightarrow \text{OH}^- + \text{H}_2 \]

### Step 4: Products of the Reaction
From the reaction, we see that the products formed are hydroxide ions (OH⁻) and hydrogen gas (H₂).

### Step 5: Identify the Correct Option
Now, we can evaluate the provided options based on the reaction we derived:
1. H⁻ + H₂O → No reaction (Incorrect)
2. H⁻ + H₂O → H₂O (Incorrect)
3. H⁻ + H₂O → OH⁻ + H₂ (Correct)
4. None of these (Incorrect)

Thus, the correct answer is option 3.

### Final Answer
When sodium hydride (NaH) is dissolved in water, the reaction that occurs is:
\[ \text{H}^- + \text{H}_2\text{O} \rightarrow \text{OH}^- + \text{H}_2 \]