Question
Question: Alum is found to contain hydrated monovalent cation [M(H2O)6]+ , trivalent cation [M¢(H2O)6]3+ and S...
Alum is found to contain hydrated monovalent cation [M(H2O)6]+ , trivalent cation [M¢(H2O)6]3+ and SO42– in the ratio of :
A
1 : 1 : 1
B
1 : 2 : 3
C
1 : 3 : 2
D
1 : 1 : 2
Answer
1 : 1 : 2
Explanation
Solution
Formula of alums contain the ions [M(H2O)6]+,
[M’(H2O)6]3+ and SO42– in the ratio 1 : 1 : 2.
Example : (i) Potash alum K2SO4 . Al2(SO4)3 . 24H2O ; (ii) Chrome alum K2SO4 . Cr2(SO4)3 . 24H2O