Arrange the following elements in order of decreasing electron gain enthalpy:

$\mathrm{B}, \mathrm{C}, \mathrm{N}$ and $\mathrm{O}$

Predict the formula of the stable binary compound that would be formed by the following pairs of elements:

Aluminium and carbon.

Predict the formula of the stable binary compound formed by the following pairs of elements:

Element with $\mathrm{Z}=113$ and fluorine.

Predict the formula of the stable binary compound formed by the following pairs of elements:

$\mathrm{Uue}$ and $\mathrm{Uus}$.