P-Block Elements Ques 261
Question: Superphosphate of lime is
[AMU 1985]
Options:
A) A mixture of normal calcium phosphate and gypsum
B) A mixture of primary calcium phosphate and gypsum
C) Normal calcium phosphate
D) Soluble calcium phosphate
Show Answer
Answer:
Correct Answer: B
Solution:
Superphosphate of lime - It is a mixture of calcium dihydrogen phosphate and gypsum and is obtained by treating phosphatic rock will conc. $ H_2SO_4 $
$ Ca_3{{(PO_4)}_2}+2H_2SO_4+5H_2O\to $ $ \underset{\text{Superphosphate of lime}}{\mathop{Ca{{(H_2PO_4)}_2}.2H_2O}}+2CaSO_4.2H_2O $
