Among the hydrides of Group-15 elements, which have the
higest bond angle?

Explanation

To determine which hydride of Group-15 elements has the highest bond angle, we will analyze the hydrides of nitrogen (NH3), phosphorus (PH3), arsenic (AsH3), and antimony (SbH3).

### Step-by-Step Solution:

1. **Identify the Group-15 Elements and Their Hydrides**:
- The Group-15 elements include nitrogen (N), phosphorus (P), arsenic (As), and antimony (Sb).
- The corresponding hydrides are NH3 (ammonia), PH3 (phosphine), AsH3 (arsine), and SbH3 (stibine).

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