NTA Abhyas NEET2020Chemistryp Block Elements (Group 13 & 14)Practice
Which is the correct formula for alum?
Options
- AK 2 S O 4 . A l 2 ( S O 4 ) 3 . 24 H 2 O
- BK 4 [ F e ( C N ) 6 ]
- CK 2 S O 4 . A l 2 ( S O 4 ) 3 . 6 H 2 O
- DN a 2 C O 3 . 10 H 2 O
Correct answer
A. K 2 S O 4 . A l 2 ( S O 4 ) 3 . 24 H 2 O
Step-by-step solution
General formula for alum is M 2 S O 4 . R 2 ( S O 4 ) 3 . 24 H 2 O M = monovalent cation ( K + , N a + . . . . ) R = Trivalent cation ( A l + 3 , F e + 3 ) Hence, K 2 SO 4 . Al 2 ( SO 4 ) 2 .24 H 2 O represent an alum.