Sodium generally does not show an oxidation state of $+2$,because of its

The five successive ionization enthalpies of an element are $800, 2427, 3658, 25024$ and $32824 \ kJ \ mol^{-1}$. The number of valence electrons in the element is

The ionisation energy of nitrogen is more than that of oxygen because :-

Ionization energy of gaseous $Na$ atoms is $495.5 \ kJ \ mol^{-1}$. The lowest possible frequency of light that ionizes a sodium atom is $(h = 6.626 \times 10^{-34} \ J \ s, N_A = 6.022 \times 10^{23} \ mol^{-1})$.

In the photoelectric effect,if the work functions of $Li$,$Na$,and $Rb$ are $2.41 \ eV$,$2.30 \ eV$,and $2.09 \ eV$ respectively,the work function of $K$ could approximately be in $eV$?

The element having the highest first ionization enthalpy is