Question

The form of phosphorus in rock phosphate is:

• A. Ca(H$_2$PO$_4$)$_2$
• B. CaHPO$_4$
• C. Ca$_3$(PO$_4$)$_2$
• D. 3(Ca$_3$(PO$_4$)$_2$)·Ca(OH)$_2$

Hint:

Rock phosphate primarily contains insoluble tricalcium phosphate, which is processed into soluble forms for agricultural use.

Answer 1

The Correct Option is D

The major form of phosphorus in rock phosphate is tricalcium phosphate combined with calcium hydroxide, represented as 3(Ca$_3$(PO$_4$)$_2$)·Ca(OH)$_2$. This form is generally insoluble in water but becomes available to plants in acidic soils or through treatment with acids to make phosphate fertilizers.