Question

Identify the correct statements.
I) $I{P}_2$ of $O$ is more than that of $N$.
II) $I{P}_2$ values of $2^{nd}$ period elements are in the order of $Li>Ne>O>F>N>B$.
III) $I{P}_1$ of $Ca$ is more than that of $K$.
IV) The IP values increase in the order $C^{4+}<B^{3+}<B{e}^{2+}<L{i}^{+}<He$.

• A. $I,II$ and $III$
• B. $I$ and $III$ only
• C. $I$ and $IV$ only
• D. $II$ and $IV$ only

Answer 1

Answer: (A)

$I,II$ and $III$

In a group, Ionization Potential decreases as we move down and in a period it's vice versa because of atomic size increases in a group and decreases from left to right in a period. But it gets reversed in a period if there is either half-filled or full-filled configuration because of stable configurations (helps for solving the first option).