Some fertilisers are described as NPK fertilisers because they contain three elements needed for healthy plant growth: nitrogen (N\text{N}N), phosphorus (P\text{P}P), and potassium (K\text{K}K).
Which two of the following compounds each contain two of these three elements?
Phosphate rock (containing calcium phosphate) is insoluble and must be treated with acids to produce soluble salts that can be used as fertilisers.
Name the soluble salts or fertiliser mixture produced when phosphate rock reacts with:
Practise AQA GCSE Chemistry The Haber process and the use of NPK fertilisers (chemistry only) with exam-style questions for Foundation and Higher tier. 10 questions covering The Haber process and Production and uses of NPK fertilisers, matched to the AQA GCSE Chemistry (8462) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.