What is the Molarity of water?

Question

I am kinda confused about this one!

Answer 1

Molarity is defined as moles of solute per liter of solution. To answer this question, you have to calculate the number of moles of water in one liter, assuming that the solution is water dissolved in itself. 1 liter of water weighs 1 kg, or 1000 g. The molecular weight of water is about 18g/mol.
Therefore:
1 mol/18g x 1000g/L = 55.6 mol/l or 55.6M

Answer 2

AT STP water has a density of 1 gram/ml. One liter of water therefore would contain 1000 grams. Taking 1000 grams and dividing by 18 grams of water per mole would give 55.5 moles. From there the molarity would be 55.5 rounding up to 55.6.

Answer 3

You usually express the concentration of a SOLUTION in terms of molarity (moles per liter). If water is the only component, you don't really have a solution.

That point aside, one mole of water has a mass of 18.00 grams and there are 1,000 grams in one liter of pure water, with small corrections for temperature and pressure. The "concentration" of water in an aqueous "solution" is therefore 1000 g/L / 18.00 g/mol = 55.6 moles per liter.

Answer 4

55.5!

Let water be called W.

1000gW/1LW x 1molW/18gW = 55.6 (rounding up!)