Question

how many atoms of oxygen are present in 10 molecules of sulphur trioxide
​

Answer 1

Given: 10 molecules of sulfur trioxide.

To find: We have to find the number of oxygen atoms.

Solution:

The chemical formula of sulfur dioxide is $SO_3$.

The atomic mass of sulfur is 32 and the atomic mass of oxygen is 16.

Thus, the molecular weight of sulfur dioxide is 32+16×3=80 grams.

Thus 1 mole of sulfur trioxide has $3×6.023×10^{23}=18.069×10^{23}$ number of oxygen atoms.

So, 10 moles of sulfur trioxide has $18.069×10^{23}×10=18.069×10^{24}$ number of oxygen atoms.

Thus 10 moles of sulfur trioxide has $18.069×10^{24}$ number of oxygen atoms.