A hydrated aluminium sulphate A12(SO4)3.xH2O, contains 8.10% of

aluminium by mass.
Find the value of x

1 answer

Find the molmass of the hydrated molecule.

molmass=12Al+3S+12O+xH2+XO where the element symbols are atomic masses.

but x*molmassH2O/above= .0810

solve for X, and have fun with algebra.