Predict from each set, the element which has the more negative electron gain enthalpy `(Delta_(eg)H^(ɵ))`. Give reasons:
a. `C` or `Si` , b. `F` or `Cl` , c. `O` or `S`

Explanation

To predict which element has a more negative electron gain enthalpy (ΔegH°) from each set, we need to consider the trends in the periodic table regarding electron affinity. Here’s a step-by-step solution:

### Step 1: Understand Electron Gain Enthalpy
Electron gain enthalpy is the energy change when an electron is added to a neutral atom in the gas phase. A more negative value indicates a greater tendency to gain an electron.

### Step 2: Analyze the Elements in Each Pair
#### a. C or Si
- **Carbon (C)** is in the second period, while **Silicon (Si)** is in the third period.
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