A 69.1-g sample of h2o contains how many molecules of water?

The number of molecules of water is calculated as follows

find the moles of water = moles=mass/molar mass

moles = 69.1g/18 g/mol = 3.84 moles

by use of Avogadro law constant

that is 1 mole = 6.02 x10^23 molecules what about 3.84 moles of water

the molecules of water = (3.84 x 6.02 x10^23) = 2.312 x10^24 molecules