Calculate the number of moles of alumunium sulfer, oxygen atoms in 9.00 moles of Alumunium sulfate, Al2(SO4)3?

Answer 1

There are 2 moles Al atoms, 3 moles S atoms, and 12 moles O atoms in 1 mole of Al2(SO4)3.
Therefore, in 9 moles Al2(SO4)3, there must be 9x2, 9x3 etc.