Softening of hard water is done using sodium aluminium silicate (zeolite) . This causes

Options

A. adsorption of `Ca^(2+)` and `Mg^(2+)` ions of hard water relpacing `Na^(+)` ions.
B. adsorption of `Ca^(2+)` and `Mg^(2+)` ions of hard water relpacing `Al^(3+)` ions.
C. both (A) and (B)
D. none of these

Answer

A

Explanation

Softening of hard water: Ion exchange resins used for softening of hard water is based upon selective and competive adsorption of ions on resins.
`Na_(2)Z+Ca^(+2) rarr CaZ+2 Na^(+)`
The organic polymers containing groups like`-COOH, -SO_(3)H` and `-NH_(2)` etc. possess the property of selective adsorption of ions from solution. These are quite usefuk in the softening of water.