Pure nutrient
Pure nutrient is the nutrient content of a fertilizer expressed as a percentage by weight . The calculation is carried out as follows: nitrogen (e.g. in nitrates or ammonium salts ) is calculated as an element , all nutrients as oxides , e.g. B. Potash as K 2 O, lime as calcium oxide (CaO), magnesium as magnesium oxide (MgO), phosphoric acid or phosphate as P 2 O 5 . For example, 100 kg of superphosphate with 18% by mass of phosphoric acid contain z. B. 18 kg of H 3 PO 4 as diphosphorus pentoxide (P 2 O 5 ) but only 8 kg of elemental phosphorus .
Individual evidence
- ^ Brockhaus ABC Chemie , VEB FA Brockhaus Verlag Leipzig 1965, p. 1196.