Quiz on Molar Mass and Elements to fluid mechanics

Which of the following is true about the molar mass of water?

• It is less than 18 g/mol

• It is exactly 18.01528 g/mol

• It is more than 20 g/mol

• It is equal to the molar mass of oxygen

One liter of water contains 55.55 moles of water molecules. Calculate the mass of the water.

• 1000 (g)

• 5500 (g)

• 1801 (g)

• 1.2 (g)

Molar mass air 28.96 g/mol and 1 liter of air at room temperature and pressure is 0.042 moles. Calculate density air.

• 1000 (kg/m3)

• 1.2 (kg/m3)

• 120 (kg/m3)

• 1200 (kg/m3)

The size of water molecule is ~0.28nm. Calculate density of water. Mr = 18.01528 g/mol. No Avo =6.022x10^23

• 1000 (kg/m3)

• 1.2 (kg/m3)

• 6022 (kg/m3)

• 325 (kg/m3)

The average diameter of air molecule is 4 angstrong (10^-10 m). Calculate density air. Mr = 28.96g/mole, Avo=6.022x10^23

• 179 (kg/m3)

• 28.96 (kg/m3)

• 1.2 (kg/m3)

• 6022 (kg/m3)