sir,was told that density of water is 1g per centimetre cube.So according to it,the density of one mole water should be same only.And we know the mass of one mole water is 18g.therefore density=mass/volume i.e. 1g/cc=18g/volume i.e. volume=18cc. but sir we also know that volume of one mole of water is 22.4 litre and this is much larger than 18cc.so sir please tell me where I am wrong and please clear my doubt as soon as possible.

Thank you.

You must realilze that, in one case, you are looking at a gas and in the other you are looking at a liquid. 18 mL of liquid water is 1 mole, 22,400 mL is 1 mole of water vapor. Quite an expansion, isn't it.