How much would two moles of dinitrogen pentoxide weigh?

The chemical formula of dinitrogen pentoxide is N2O5 . We can calculate its molar mass (mass of one mole) by multiplying the subscript of each element by its molar mass (atomic weight on the Periodic Table in grams/mole) and adding them together.

Molar mass N2O5 =(2 x 14 g/mol N) + (5 x 16 g/mol O) = 108 g/mol N2O5

The mass of two moles of N2O5 is (2 x 108 g/mol N2O5 ) = 216 g