So, To calculate the mass percentage of dinitrogen pentoxide (N2O5) we will first calculate the molar weight of the molecule. The mass percentage will be calculated with the following equation:
[tex]\text{Mass percentage = }\frac{\text{Molar Mass oxygen}}{MolarmassmoleculeN_2\text{O}_5}\times100[/tex]Molar mass will be:
Element Atomic Mass #Atoms Mass
N 14.0067 2 28.0134 g/mol
O 15.9994 5 79.997 g/mol
Total mass = 28.0134 + 79.997 = 108.0104 g/mol
[tex]\text{Mass percentage = }\frac{\text{7}9.997}{108.0104}\times100\text{ = }74.064\text{ percent}[/tex]