……….method is
used to remove the temporary hardness of water on large scale.
a) Clark’s
b) Coulomb
c) Charle’s
d) Boyle’s
Clark’s method is a ………….. method.
a) physical
b) chemical
c) both a & b
d) none of these
The carbonates of ……are insoluble in water.
a) calcium
b) magnesium
c) both a & b
d) none of these
Permanent hardness of water can only be removed by using chemicals, which convert soluble salts into ……Salts on precipitation.
a) soluble
b) insoluble
c) chemical
d) all of these
The ……….removes the permanent hardness of water.
a) Na2CO3
b) Na2SO4
c) KNO3
d) NaCl
The Na2CO3 reacts with the soluble calcium & magnesium chloride and sulphate and converts them into insoluble…………..
a) calcium carbonate
b) magnesium carbonates
c) both a & b
d) none of these
