A 75.0 mL sample of water is heated to its boiling point. How much heat (in kJ ) is required to vaporize it?

Given :

A 75.0 mL sample of water is heated to its boiling point.

To Find :

The heat (in kJ ) is required to vaporize it .

Solution :

Heat of vaporization of water , .

Molar mass of , .

Density of water , .

Mass of 75 ml of water sample , .

Moles of 75 g water = .

Now , heat required to vaporize 4.17 mol of water :

Therefore , heat required to boil 75 ml sample of water is 169.51 kJ.

Hence , this is the required solution .  

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