Question

With hard water, ordinary soap forms curdy precipitate of:

• A. $(RCOO{)}_{2}Ca$
• B. $(RCOO{)}_{2}Mg$
• C. Both (a) and (b)
• D. None of these

Answer 1

Answer: (C)

Both (a) and (b)

Hardness in water is due to dissolved sulphate, chlorides and bicarbonates of calcium and magnesium. When such type of water is used for cleaning clothes with soap (.e., sodium stearate) a curdy precipitate of calcium and magnesium salts are formed.

Hence, the correct option is $\text{C}$