How do you calculate the mass of one mole of water

Question

Calculate the mass of one mole of water.

 

Given that the density of water is 1 g/mL, how many mL is that. 

 

I need help. I don't understand.

Answer 1

Water is H2O. So the mass of 1 mole is the sum of the atomic masses. That would be 2x1 =2 for the 2 H + 16 for O for a total molar mass of 18 g. So 1 mole if water has a mass of 18 g. 

 

18 g x 1 ml/1 g = 18 mls