<span>There are 2 atoms of Al in the unit formula Al₂(SO₄)₃, so there are 4x2 = 8 atoms of Al in 4 unit formulas of the same compound. </span>
<span>2) Sulfur: </span>
There are 3 atoms of S in the unit formula <span>Al₂(SO₄)₃, so there are 4x3 = 12 atoms of S in 4 unit formulas of the same compound </span>
3) Oxygen:
<span> </span><span>There are 4x3 = 12 atoms of O in the unit formula </span><span>Al₂(SO₄)₃, so there are 4x12 = 48 atoms of O in 4 unit formulas of the same compound.</span>
<span>To calculate the number of moles of aluminum, sulfur, and oxygen atoms in 4.00 moles of aluminum sulfate, al2(so4)3. We will simply inspect the "number" of aluminum, sulfur, and oxygen atoms available per one mole of the compound. Here we have Al2(SO4)3, which means that for every mole of aluminum sulfate, there are 2 moles of aluminum, 3 (1 times 3) moles of sulfur, and 12 (4x3) moles of oxygen. Since we have four moles of Al2(SO4)3 given, we simply multiply 4 times the moles present per 1 mole of the compound. So we have 4x2 = 8 moles of Al, 4x3 = 12 moles of sulfur, and 4x12 = 48 moles of oxygen.
