Question

Write the molecular formula of the following compounds of Sulphur trioxide.

Find the number and names of elements present in them and calculate their molecular masses.

Answer 1

Sulphur trioxide

1. A molecule of sulphur trioxide is represented by the formula SO₃.
2. The elements present in it are sulphur dioxide and oxygen.
3. One molecule of sulphur trioxide has one atom of sulphur and three atoms of oxygen.
4. Molecular mass of sulphur trioxide (SO₃)
   = 32 + 3 x 16
   = 32 + 48 = 80 amu.