The order of negative electron gain enthalpy of $\mathrm{Li}, \mathrm{Na}$, $\mathrm{S}, \mathrm{Cl}$ is

The period and group numbers of the element having maximum electronegativity in the long form of periodic table respectively, are

Electronic configurations of four elements $A, B, C, D$ are given below

(A) $1 s^2 2 s^2 2 p^6 3 s^1$

(B) $1 s^2 2 s^2 2 p^6 3 s^2 3 p^1$

(C) $1 s^2 2 s^2 2 p^6 3 s^2$

(D) $1 s^2 2 s^2 2 p^6 3 s^2 3 p^2$

The correct order of first ionisation enthalpy of these elements is

The correct order of the non-metallic character among the elements $\mathrm{B}, \mathrm{C}, \mathrm{N}, \mathrm{F}$ and Si is