How many oxygen atoms are there in 750 moles of diphosphorus

How many oxygen atoms are there in 7.50 moles of diphosphorus pentoxide?

Solution

diphosphorous pentoxide exists as P4O10.

Its molar mass is 283.886g/mol

Thus in each molecule of P4O10 we have 10 oxygen atoms.

and each mole of P4O10 has 10 moles of oxygen atoms.

Hence 7.5 moles of P4O!0 has 10x 7.5 moles of oxygen atoms.

The number of O atoms in 7.5moles of P4O10 = 7.5x10 x 6.02x10²³

= 4.515x10²⁵ atoms