Consider the elements `N, P, O` and `S` and arrange them in order of increasing negative electron gain enthalpy,

Explanation

To arrange the elements Nitrogen (N), Phosphorus (P), Oxygen (O), and Sulfur (S) in order of increasing negative electron gain enthalpy, we can follow these steps:

### Step 1: Understand Electron Gain Enthalpy
Electron gain enthalpy is defined as the amount of energy released when an electron is added to a gaseous atom. A more negative value indicates a greater tendency of the atom to gain an electron.

### Step 2: Identify the Groups and Periods
- **Nitrogen (N)** and **Oxygen (O)** are in the second period of the periodic table.
- **Phosphorus (P)** and **Sulfur (S)** are in the third period.
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