Question

Atomic size across a period increases with increase in nuclear charge of element.

• A. True
• B. False

Answer 1

The correct option is B False

Moving from left to right across a period, electrons are added one at a time to the outer energy shell. Electrons within a shell cannot shield each other from the attraction to protons. Since the number of protons is also increasing, the effective nuclear charge increases across a period. This causes the atomic radius to decrease.