Question

How many moles do 12.0 x 10^23 molecules of H2O constitute? (Points : 3)
1.99 moles
5.98 moles
7.22 x 1047 moles
2.16 x 1048 moles

Answer 1

Use Avogadro's number: 6.022 * 10^23 units (molecules/atoms/formula units) in one mole.

Answer 2

\[\color{green}{\text{number of moles} = \frac{\text{number of molecules}}{\text{Avogadro's constant}}}\]