Question

Which of the following given fertilizers contains the highest Phosphorus content?

• A. Superphosphate
• B. Triple Superphosphate
• C. Both a and b
• D. None of the above

Answer 1

The correct option is B Triple Superphosphate

Superphosphate is the product of the reaction:
$C{a}_3(P{O}_4{)}_2+2H_{2}S{O}_4\to Ca(H_{2}P{O}_4{)}_2+2CaS{O}_4$

In the following reaction, we use phosphoric acid instead of sulphuric acid. The phosphatic rock used is called Fluorapatite - $C{a}_5(P{O}_4{)}_{3}F$. Although the product also contains some $HF$, it is removed as $H_{2}Si{F}_6$ when $HF$ reacts with Silica impurities.

$C{a}_5(P{O}_4{)}_{3}F+7H_{3}P{O}_4\to 5Ca(H_{2}P{O}_4{)}_2+HF$

The product of the above reaction is called triple - superphosphate. It contains more Phosphorus content than superphosphate and is more widely used.