Question: how many molecules of water are there in 0.500 moles of water?
Answer: How many molecules of H2O are present in 0.500 mol of water? 1 mol of water contains 6.022 × 1023 H2O molecules Therefore 0.500 mol contains 0.500 × (6.022 × 1023) = 3.01 × 1023 H2O molecules.