Boiling Point of hard water is more than that of distilled water at the same atmospheric pressure why
Answers
Hard water has the impurities of Mg and Ca in it which increases it's boiling point than ordinary H2O whereas distilled just contain H2O so it's B.P. remains same as 100 Degree.
This is based on the concept of elevation in boiling point in case of solution as compared to that of pure water.
Hard water contains several impurities in the form of carbonates,chlorides,etc. and therefore while boiling these pose a barrier and hence, a greater temperature is required for it to boil.This is associated with a change in vapour pressure of pure water on addition of solutes into it.
On the other hand, pure water has nothing to restrict it and it's vapour pressure remains constant and so it boils at a lower temperature compared to that of the previous case.