Give reasons :Aluminium is a reactive metal but is still used for packing food articles

Give reasons:

  1. Aluminium is a reactive metal but is still used for packing food articles.
  2. Red litmus paper turns blue when touched with aqueous solution of magnesium oxide.

Answer:

  1. On exposure to air, aluminium forms a hard protective layer of aluminium oxide (A1203) which prevent further oxidation.
  2. Magnesium oxide is an oxide of a metal, so, it is basic in nature. Due to its basic character it turns red litmus paper blue when touched with its aqueous solution.