Al2(SO4) 3 solution of 1 molal concentration is present is 1 litre solution of 2.684 gm/ cc. How many moles of BaSO4 would be precipitated on adding BaCl2 in excess.
The density of the solution is 2.684 g/cc, which includes both the solute Al2(SO4)3 and the solvent water. So, deducing the density of water which is ~ 1 g/cc, we will have 1.684 g/cc of Al2(SO4)3 .
So, in a litre of solution we have 1.684 x 1000 = 1684 g of Al2(SO4)3 .
Moles of Al2(SO4)3 =
For 1 mol of Al2(SO4)3 we will have 3 mol of BaSO4, therefore, for 4.92 mol of Al2(SO4)3 it will produce 3 x 4.92 = 14.76 mol of BaSO4.
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