Determine the mass of oxygen in a 3.6 g sample of Al2(SO4)3.
for the calculation of mass of oxygen in Al2(SO4)3, first calculate the no of moles of Al2(SO4)3 from 3.6g .
No of mole of Al2(SO4)3= given mass / molecular mass
Al2(SO4)3 has 12 Oxygen atoms,then the no of moles of oxygen = 12 0.01
mass of 0.12 mol Oxygen =0.1216 ( 16 is atomic mass of oxygen)