Bravo! You are right.

By looking at the formula,

In 1 mole of sulphuric acid, there are

  • 2 moles of hydrogen atoms,
  • 1 mole of sulphur atoms and
  • 4 moles of oxygen atoms.

So, in 3 moles of sulphuric acid, there will be

  • 2 x 3 = 6 moles of hydrogen atoms,
  • 1 x 3 = 3 moles of sulphur atoms and
  • 4 x 3 =12 moles of oxygen atoms.