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[chiarettinaa92]

A mixture X consists only of FeSO4, Na2SO4 and Al2 (SO4) 3. To oxidate 5 g of the mixture, we need 52.7 moles of a 0.05 M solution of KMnO4 in an acidic environment. Then dissolving in H2O X 10 g of a solution is obtained whose volume is 850 mL, and which has an osmotic pressure equal to 3.647 torr at 25 ° C. Calculate the% by weight of X (R:% FeSO4 = 40%;% Al2 (SO4) 3 = 20%;% Na2SO4 = 40%) . I don't know how I can solve that...