Q34 / 125 · BITSAT 2015 · Chemistry
Which one the following removes temporary hardness of water?
- Correct answerASlaked lime
- B$\quad$ Plaster of Paris
- CEpsom
- DHydrolith
Solution
This method is known as Clark's process. In this method temporary hardness is removed byadding lime water or milk of lime.
$$
\mathrm{Ca}(\mathrm{OH})_{2}+\mathrm{Ca}\left(\mathrm{HCO}_{3}\right)_{2} \longrightarrow \underset{\mathrm{ppt} .}{2 \mathrm{CaCO}_{3}} \downarrow+2 \mathrm{H}_{2} \mathrm{O}
$$
Hence, the correct answer is option: 'A'.