Over 95% of the phosphate rock mined in the US is used to manufacture phosphoric acid and phosphate-based fertilizers. The remaining phosphate rock is used for the production of white phosphorus. 

(a) Give equations to show how phosphate rock is converted to phosphoric acid and to white phosphorus.

(b) Phosphate rock is converted to superphosphate fertilizers by treatment with concentrated H₂SO₄ and to triple superphosphate by reaction with H₃PO₄. What is the chemical composition of these fertilizers? Why are they suitable for use as fertilizers when phosphate rock itself is not? 

(c) What is meant by condensation of phosphates? 

(d) What is the role of Na₅[P₃O₁₀] in detergents? Why is its use in decline, and what substitute is now favoured? Explain how the newer material carries out the role originally played by Na₅[P₃O₁₀].