(a) Arrange the first three members of the halogen family in their increasing order of electronegativity. Give the reason for your answer.
(b) State and explain what happens when chlorine reacts with starch iodide paper.
Explanation
(a) Bromine — Chlorine — Fluorine Increasing order of electronegativity. The above order is as a result of their decreasing order of atomic size from bromine to fluorine. The smaller the atom, the more the atom is capable of attracting electron to itself.
(b) Iodine is precipitated as the molecular iodine by chlorine gas because chlorine, the more electronegative halogen than iodine displaces the iodine from its seat of combination in the starch iodine paper.