Method for quickly identifying commonly used fertilizers

First, nitrogen fertilizer; urea, ammonium sulfate, ammonium bicarbonate, ammonium chloride and other fertilizers on the appearance of urban white crystals, can be identified by the following methods.

( 1 ) Burning method; ammonium nitrogen will decompose after being heated. Therefore, at the time of identification, a small amount of fertilizer is placed on the iron piece and burned on the flame. If thicker produced having offensive odors and without leaving high purity nitrogen Accession residue; if more residues, indicating a low nitrogen content.

( 2 ) Dissolution method; ammonium nitrogen can be dissolved in water. A small amount of chemical fertilizer can be used, and a small amount of water can be added. If all is dissolved, the nitrogen content is high in purity, and if it is partially or completely insoluble, it contains more impurities.

( 3 ) Add slaked lime mixing method; mix a small amount of chemical fertilizer with slaked lime, stir, and immediately smell the strong nitrogen fertilizer, indicating high nitrogen content.

(4) color reaction method; ammonium bicarbonate, ammonium carbonate, alkaline, red radish skin can be (or was amaranth red) after boiling, taking the supernatant, a small amount of ammonium carbonate into the clear supernatant, if red The turnip turn from purple to light green (or red amaranth juice from red to yellowish green) is pure.

Second, phosphate fertilizer; the appearance of superphosphate should be gray granular, acidic, and partially acceptable. Jiangshao two calcium phosphate adding a small amount of water, if there is partially dissolved, can initially conclude that superphosphate. Be tested in the above-described red radish skin juice (juice or amaranth red), if the solution changed from purple to bright red (amaranth red or from red to dark red juice), calcium phosphate described good quality.