# Question 18ede

Oct 3, 2015

Options (1) and (2) are correct.

#### Explanation:

Right from the start, the definition of electronegativity excludes option (3) from the answer.

Electronegativity is the ability of an atom to attract electron density in a bond with another atom. This means that electronegativity cannot be considered a property of a solitary atom, but rather a property of an atom when it's part of a molecule.

Ionization energy and electron affinity, on the other hand, are properties that can be attributed to solitary atoms.

Ionization energy tells you how much energy is required to remove one mole of electrons from one mole of atoms in the gaseous state.

In essence, ionization energy tells you what the energetic cost of forming cations is for a gaseous atom

${\text{X" + color(blue)("energy") -> "X}}^{+} + {e}^{-}$

Electron affinity tells you how muc henergy is releseaed when one mole of atoms is added to one mole of atoms in the gaseous state.

Electron affinity tells you how much energy will be released when an anion is being formed

"X" + e^(-) -> "X"^(-) + color(blue)("energy")#

So, as a conclusion, ionization energy and electron affinity are properties that describe solitary atoms in the gaseous state.

On the other hand, electronegativity only comes into play when an atom is bonded to another atom.