How many molecules are in 237 g (about a cup of water?

Any element or compound contains 6.0221409e+23molecules or atom per mole of it. In this case, we convert first the given mass of water by dividing it by 18 g/mol, the molar weight of water. we multiply then to the Avogadro's number that is then equivalent to 7.9289667e+24 molecules of water.