The most stable hydride is

Options

A. `B_(2)H_(6)`
B. `AlH_(3)`
C. `GaH_(3)`
D. `InH_(3)`

Explanation

To determine the most stable hydride among the given options (B2H6, AlH3, GaH3, InH3), we can follow these steps:

### Step 1: Identify the Hydrides
First, we need to identify the hydrides of the elements in the boron family (Group 13). The hydrides are:
- Boron (B): B2H6 (Diborane)
- Aluminum (Al): AlH3 (Aluminum Hydride)
- Gallium (Ga): GaH3 (Gallane)
- Indium (In): InH3 (Indium Hydride)

### Step 2: Analyze Stability Trends
Next, we analyze the stability of these hydrides. Generally, the stability of hydrides in a group decreases as we move down the group in the periodic table. This is due to the increase in atomic size and the corresponding decrease in bond strength between the central atom and hydrogen.

### Step 3: Compare Bond Strengths
- **B2H6**: The bond between boron and hydrogen is relatively strong due to the smaller size of boron, leading to a more stable compound.
- **AlH3**: The bond strength decreases compared to B2H6 as we move down to aluminum.
- **GaH3**: The bond strength further decreases as we move to gallium.
- **InH3**: The bond strength is the weakest among these hydrides due to the larger atomic size of indium.

### Step 4: Conclusion
Since the stability of hydrides decreases down the group, we conclude that B2H6 (Diborane) is the most stable hydride among the options provided.

### Final Answer
The most stable hydride is **B2H6**.

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