(a) `Al` is a good reducing agent. Explain.
(b) A metallic element, `M`, forms two stable chlorides with formula `MCl` and `MCl_(3)` respectively. Where the element `M` is to be placed in the periodic table ?

Explanation

(a) Reducing agent can easily lose electron and get oxidised since `Al`has low ionisation enthloy and has `+ ve` reduction potential, it acts as good reducing agent.
(b) Metal, `M`, forms chlorides `- MCl` and `MCl_(3)`. The oxidation state of `M` in `MCl` is `+ 1` and in `MCl_(3)` is `+ 3`. This implies that metal `M` has three electrons in its valence shell and `M` belongs to group `13`, i.e. boron family.