A sample of hardwater was found to loose its hardness on boiling. Name the type of hardness associated with this sample.

Hard water does not give ready leather with soap. What are the two types of hardness?

. A sample of drinking water was found to be severely contaminated with chloroform '(CHCl_3)' supposed to he a carcinogen. The level of contamination was 15 ppm (by mass):i. express this in percent by mass ii. determine the molality of chloroform in the water sample.

A sample of cold river water does not easily give lather with soap, but on boiling it does. Evaluate and write the chemical equation involved