Periodic Trends in Properties
First Ionisation Enthalpy of p-block Element
A ‘p’-block element (E) and hydrogen form a binary cation (EHx)+, while EH3 on treatment with K2HgI4 in alkaline medium gives a precipitate of basic mercury(II)amido-iodine. Given below are first ionisation enthalpy values (kJ mol–1) for first element each from group 13, 14, 15 and 16. Identify the correct first ionisation enthalpy value for element E.