Question

and impurity present in water dash its freezing point​

Answer 1

Explanation:

Depression of freezing point by impurities. The presence of impurities lowers (depresses) the freezing point of a liquid. The impurities lower the vapour pressure of the solution so that ice can melt at a lower temperature

Answer 2

The impurity present in water increases its freazing point.

I.e Freazing point increase above 0℃ - 4℃.

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