Which of the following correctly represents the mole ratio between Al2(SO4)3 and CuSO4?
3 CuSO4 + 2 Al → Al2(SO4)3 + 3 Cu

1 mol Al2(SO4)3 : 3 mol CuSO4
2 mol Al2(SO4)3; 3 mol CuSO4
3 mol Al2(SO4)3: 2 mol CuSO4
2 mol Al2(SO4)3 : 3 mol CuSO4