Question

Which of the following orders is not correct for the given property?

• A. Li<Na<K - metallic radius
• B. Br<F<Cl - electron gain enthalpy
• C. C<N<O - first ionization enthalpy
• D. Mg$^{2+}$<Na$^+$<F$^-$ - ionic radius

Hint:

Ionization enthalpy increases across a period and decreases down a group.

Answer 1

The Correct Option is C

For ionization enthalpy, oxygen has higher ionization enthalpy than nitrogen due to its smaller size and higher effective nuclear charge. Hence, the correct order should be N<O<C.