# Question #5f528

Jun 23, 2017

The process involving the maximum amount of energy is c) $\text{O"^"-" + "e"^"-" → "O"^"2-}$.

#### Explanation:

The first electron affinity is the amount of energy released or absorbed when an electron is added to a neutral atom in the gaseous state.

$\text{X(g)" + "e"^"-" → "X"^"-""(g)}$

As you might expect, the electron affinity becomes more negative from left to right across a row in the Periodic Table.

Thus, the order of first electron affinities is

$\text{N < O < F}$

The numbers are +7, -141, and—328 kJ/mol, respectively.

The second electron affinity is the energy required to add an electron to a
gaseous 1- ion.

$\text{X"^"−""(g)" + "e"^"-" → "X"^"2-""(g)}$

You are forcing an electron into an already negative ion. It's not going to go in willingly!

Thus, for the second electron affinity of oxygen,

$\text{O"^"-""(g)" + "e"^"-" → "O"^"2-""(g)"; EA = "+844 kJ/mol}$

This is the maximum amount of energy absorbed or released.

Hence, the correct answer is c).