What are the different types of impurities present in water?

A) Different types of impurities are

i) Dissolved impurities:

a) Inorganic salts 

 i) Cations:Ca+2,Mg+2, Na+,K+,Fe+2, Al+3 traces of

Zn+2 etc

 ii) anions: Cl-,SO42-, NO3-,HCO3-&sometimes F-&NO2-

b) Gases: CO2,O2, N2 oxides of N2&sometimes NH3,H2S

c) Organic salts

ii) Suspended impurities

a) Inorganic: Clay and sand

b) Organic: Oil globules, Vegetable and Animal matter

iii) Colloidal impurities: Finely divided Clay & Silica, Products from 

organic waste

iv) Bacterial impurities: Bacteria, other microorganisms and other forms of animal &vegetable life