A ‘p’-block element \( \mathrm{(E)} \) and hydrogen form a binary cation \( (\mathrm{EH_x})^{+} \), while \( \mathrm{EH_3} \) on treatment with \( \mathrm{K_2HgI_4} \) in alkaline medium gives a precipitate of basic mercury(II) amido-iodine. Given below are first ionisation enthalpy values (\( \mathrm{kJ\,mol^{-1}} \)) for first element each from group \( 13 \), \( 14 \), \( 15 \) and \( 16 \). Identify the correct first ionisation enthalpy value for element \( \mathrm{E} \).
