Question

Identify the wrong statement in the following. [CBSE AIPMT 2012]

• A. Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius
• B. Amongst isoelectronic species, greater the negative charge on the anion, larger is the ionic radius
• C. Atomic radius of the elements increases as one moves down the first group of the periodic table
• D. Atomic radius of the elements decreases as one moves across from left to right in the 2nd period of the periodic table

Answer 1

The correct option is A Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius

Atomic radius of the elements decreases across a period from left to right due to increase in effective nuclear charge. On moving down a group. since, number of shells increases, so atomic radius increases.
Amongst isoelectronic species, ionic radius increases with increase in negative charge or decrease in positive charge.