Question

calculate number of moles of 1L of H20 whose density of water is equal to 0.5gm/mol​

Answer 1

Answer:

The formula for water is H2O , which means two hydrogen atoms and one oxygen. We calculate the molecular mass of water by adding the atomic masses of the atoms. Looking at a periodic table, we see the mass of hydrogen is 1, and oxygen is 16, so water is 2 x 1 + 16 = 18.

A mole is the quantity of a substance where the mass in grams equals the molecular mass, so one mole of water weighs 18g. It just so happens that at standard temperature and pressure, the density of water is 1g per mL. A liter of water is 1000g of water.

To get the number of moles per liter of water, we divide the mass of 1L of water (1000g) by the mass of a mole of water (18g / mole). 1000 / 18 = 5559 moles.