11.22. Give reasons:
(vi) Aluminium utensils should not be kept in water overnight.
Aluminium utensils should not be kept in water overnight because they react with water with the help of atmospheric oxygen and form an oxide layer on the surface of the utensils. When we kept water on these utensils for a long period of time, some amount of oxide dissolved in the water, which is harmful (water becomes basic in nature).