Question

Do you expect different products in solution when aluminium (III) chloride and potassium chloride treated separately with (a) normal water, (b) acidified water and ( c) alkaline water? Write equations wherever necessary.

Answer 1

Both the compounds are salts and they react in different manner with water of different nature.
(a) Aluminium (III) chloride of `AlCl_(3)` will react with water as follows:
`AlCl_(3)+3H_(2)O to Al(OH)_(3)+H_(2)(g)`
The reaction is known as hydrolysis.
(*)In normal water, Both `(Al(OH)_(3))` and HCl will be present
(*) In alkaline water, HCl will be neutralised by the alkali added. Therefore it will contain mainly `Al(OH)_(3)` and will be alkaline in nature.
(*) In acidic water. In this medium, `Al(OH)_(3)` will be neutralised by the acid added. Therefore, water will contain mainly HCl and will be acidic in nature.
(b) Potassium chloride is a salt of strong acid and strong base. It will remain as such under all the conditions and will not undergo and chemical reaction.