The substance that has the lowest boiling point is

The structure of silicon $(IV)$ oxide belongs to the type

$I_2$ molecules are held in the solid lattice by $...................$

The hydration energies of $K^{+}$ and $Cl^{-}$ are $-x$ and $-y$ $kJ / mol$ respectively. If the lattice energy of $KCl$ is $-z$ $kJ / mol$,then the heat of solution of $KCl$ is $:$

Which of the following substances has the highest melting point?

The distance between two adjacent carbon atoms is maximum in