Question

Correct orders of $1st$ I.P. are -

(i) Li < B < Be < C

(ii) O < N < F

(iii) Be < N < Ne

• A. (i), (ii)
• B. (ii), (iii)
• C. (i), (iii)
• D. (i), (ii), (iii)

Answer 1

The correct option is D

(i), (ii), (iii)

Down the group ionization potential (ionization enthalpy) decreases with increase in size.

Across a period, ionization potential decreases and then increases at the noble gasses.

Elements of group 2(IIA) have I.E more than that of group 13(IIA) as they have completely filled 's' orbital. Be > B

Elements of group 15(VA) have more than that of group 16(VIA) as they have half filled 'P' subshell. N > O

Inert gas elements have the highest I.P in a given period due to a stable electronic configuration.