Time left 0:3 A (3.6500 g) of impure ammonium aluminium sulfate (NH4Al(SO4)2)) was treated with ammonia (NH3(aq)) producing hydrous alumina Al2O3.XH20. The collected precipitate was filtered, washed, and ignited at 1000 C to give 0.4935 g Al2O3 (Mw 101.9635 g/mol). Determine: a. % Al2O3. (2 Marks) b. %AI. (3 Marks) C. Express concentration of Al in ppm. (2 Marks)