Answer: Na+ has a higher electron affinity than Cl.
The energy released when an electron is added to a neutral gaseous atom is known as electron affinity.
- The electron affinity increases across a period while it decreases down a group.
- In halogens chlorine posses the highest electron affinity in the periodic table.
- As atomic radii increases, electron affinity increases.
- As nuclear charge increases, electron affinity increases.
- It decreases down a group and increases across a period.
- The unit for electron affinity is kilo joules per mole.