Question #4056c

1 Answer
Oct 19, 2014

The value of n = 18.

The percentage of anhydrous aluminium sulfate must be 100 - 48.65 = 51.35 %

The Mr of aluminium sulfate is (2 x27) +[32 +(4 x16)] x 3 = 342

The Mr of water (H_2O) is (1+1) + 16 = 18

Ratio in moles is:

51.35/342 : 48.55/18

rArr 0.15 : 2.7

rArr 1 : 18

So the formula of hydrated aluminium sulfate , in this case, is

Al_2(SO_4)_(3).18H_2O