An element X of group 15 and period 2 exists as diatomic molecule. It combines with hydrogen and forms ammonia in the presence of a suitable catalyst.
Write the electronic configuration of X and count the number of valence electrons.

Explanation

To solve the question, we need to identify the element X from group 15 and period 2, determine its electronic configuration, and count the number of valence electrons.

### Step-by-Step Solution:

1. **Identify the Element:**
- The element X is in group 15 (the nitrogen family) and period 2 of the periodic table. The elements in group 15 include nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi). Since we are looking for an element in period 2, the only element that fits this description is nitrogen (N).

2. **Determine the Electronic Configuration:**
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