Question
Question: Deionized water is obtained by passing hard water through :...
Deionized water is obtained by passing hard water through :
A
Zeolite.
B
Cation exchanger.
C
Anion exchanger.
D
Both cation and anion exchanger one after the other.
Answer
Both cation and anion exchanger one after the other.
Explanation
Solution
Hard water passed through cation exchange resin which releases H+ and then passed through anion exchanges resin which releases OH–
2RH(s) + M2+(aq)
MR2(s) + 2H+(aq).¼ (i)
[M2+ = Ca2+/Mg2+]
RNH2(s) + H2O(l) RNH+3 + OH–(s)
RNH+3. OH–(s) + X–(aq) RNH3X– + OH–¼ (ii)
[X– = Cl–, HCO–3, SO2–4 etc.]
OH– neutralise the H+ released in the cation exchange in
(eq i)
H+(aq) + OH–(aq) H2O(l)