If we consider ionization enthapies of elements in the second period from Li , they ordinarily increase but Be and N have higher ionization enthalpies than B and O respectively which succeed them. Why is it so ?

Explanation

To understand why beryllium (Be) and nitrogen (N) have higher ionization enthalpies than boron (B) and oxygen (O) respectively, we can analyze the electronic configurations and stability of these elements.

### Step-by-Step Solution:

1. **Definition of Ionization Enthalpy**:
- Ionization enthalpy is the amount of energy required to remove an electron from an isolated gaseous atom.

2. **General Trend in the Second Period**:
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