i. Reaction with hydrogen: Alkali metals react with hydrogen at high temperature to form the Corresponding metal hydrides.
ii. Reaction with halogens: All the alkali metals react vigorously with halogens to produce their ionic halide salts.
[Note: As we move down the group, the reactivity of alkali metals towards hydrogen and halogens decreases in the following order: Li > Na > K > Rb > Cs.]
