Question

The temporary hardness in water is due to ____________

(a) OH^–

(b) CO3^2-

(c) H^+

(d) HCO3^–

This question was posed to me by my college professor while I was bunking the class.

Question is from Alkalinity of Water and its Estimation topic in section Water and its Treatment of Engineering Chemistry II

Answer 1

Correct option is (d) HCO3^–

For explanation I would say: The temporary hardness in water is due to HCO3^–. It can easily be removed by mere action of boiling.