Which of the following statements are true?

A. Unlike Ga that has a very high melting point, Cs has a very low melting point.

B. On Pauling scale, the electronegativity values of N and Cl are not the same.

C. $\mathrm{Ar}, \mathrm{K}^{+}, \mathrm{Cl}^{-}, \mathrm{Ca}^{2+}$, and $\mathrm{S}^{2-}$ are all isoelectronic species.

D. The correct order of the first ionization enthalpies of $\mathrm{Na}, \mathrm{Mg}, \mathrm{Al}$, and Si is $\mathrm{Si}>\mathrm{Al}>\mathrm{Mg}>\mathrm{Na}$.

E. The atomic radius of Cs is greater than that of Li and Rb.

Choose the correct answer from the options given below :

Which among the following electronic configurations belong to main group elements?

A. $[\mathrm{Ne}] 3 \mathrm{~s}^1$

B. $[\operatorname{Ar}] 3 \mathrm{~d}^3 4 \mathrm{~s}^2$

C. $[K r] 4 d^{10} 5 s^2 5 p^5$

D. $[\operatorname{Ar}] 3 \mathrm{~d}^{10} 4 \mathrm{~s}^1$

E. $[R n] 5 f^0 6 d^2 7 s^2$

Choose the correct answer from the option given below :

The correct decreasing order of atomic radii (pm) of $$\mathrm{Li}, \mathrm{Be}, \mathrm{B}$$ and $$\mathrm{C}$$ is

Match List I with List II :

Identify the correct answer from the options given below :