Which of the following pairs show reverse properties on moving along a period from left to right and from top to down in a group?

Options

(a) Nuclear charge and electron affinity
(b) ionisation energy and electron affinity
(c) Atomic radius and electron affinity
(d) None of the above

Correct Answer:

Atomic radius and electron affinity

Explanation:

Atomic radius increases from top to bottom in a group while decreases from left to right in a period, on the otherhand electron affinity shows reverse trends, i.e., decreases from top to bottom in a group and increases from left to right in a period.