Recall that phosphate rock is obtained by mining but cannot be used directly as a fertiliser. (Chemistry only)

In the subtopic Production and uses of NPK fertilisers, this learning objective focuses on recall that phosphate rock is obtained by mining but cannot be used directly as a fertiliser. (Chemistry only). Within The Haber process and the use of NPK fertilisers, students should explain this idea in the exact curriculum context rather than as an isolated fact. Approved keywords for this objective include chemistry only, phosphate rock, and mining. phosphate rock means a naturally occurring mineral that is mined but cannot be used directly as a fertiliser. Avoid students often think that phosphate rock can be used directly as a fertiliser; instead remember that phosphate rock must be treated to produce soluble salts before it can be used as a fertiliser. For exam answers, remember that phosphate rock is mined but must be treated before use as a fertiliser.