What happens when:
a. Hot and concentrated NaOH solution reacts with `I_(2)`.
b. White phosporus is heated with caustic soda.
c. Excess of caustic soda reacts with zinc sulphate solution.
d. Excess of caustic soda is added to `AICI_(3)` solution.
e. Sodium is heated strongly in oxygen and the product is treated with `H_(2)SO_(4)`.