Identify the incorrect statement from the following?

Atomic numbers of three elements $E_1, E_2$ and $E_3$ of periodic table are $Z_1, 50$ and $Z_2$ respectively. From the position of the elements shown in figure, the values of $\left(Z_2-Z_1\right)$ is

Electron gain enthalpy values $\left(\Delta_{\mathrm{cg}} H\right)$ (in $\mathrm{kJ} \mathrm{mol}^{-1}$ ) of elements $X, Y$ and $Z$ are $-349,-200$ and -295 respectively. $X, Y$ and $Z$ are respectively

Observe the following list of molecules. Number of polar and non-polar molecules are respectively

$\mathrm{NH}_3, \mathrm{BF}_3, \mathrm{NF}_3, \mathrm{H}_2 \mathrm{~S}_2, \mathrm{CO}_2, \mathrm{CH}_4, \mathrm{CHCl}_3, \mathrm{H}_2 \mathrm{O}$