The aluminum present in $1200$ grams of an impure sample of aluminum ammonium sulfate was precipitated

as aqueous ammonia, as Al$2$O$3.$ Hydrated Xh$2$O$.$ The precipitate was filtered and calcined at $1000\backslash$deg C to

form anhydrous Al$2$O$3,$ whose weight was $0\mathrm{.}1798$ grams. Express the results of this analysis in terms

of:

to$.$ Percentage of NH$4$Al$($SO$4)2.$

b$.$ Al$2$O$3$ percentage

c$.$ Al Percentage