Chemistry is widely used in industrial and agricultural production and daily life. (1) Please point out that potassium chloride, ammonium sulphate, calcium phosphate, ammonium dihydrogen phosphate are

Chemistry is widely used in industrial and agricultural production and daily life. (1) Please point out that potassium chloride, ammonium sulphate, calcium phosphate, ammonium dihydrogen phosphate are four commonly used agricultural fertilizers, namely, potassium chloride, ammonium sulphate, calcium phosphate and ammonium dihydrogen phosphate. (1) potassium chloride contains potassium, belongs to potash; ammonium sulfate contains nitrogen, belongs to nitrogen fertilizer; calcium phosphate contains phosphorus, belongs to phosphorus fertilizer; ammonium dihydrogen phosphate contains phosphorus and nitrogen, belongs to compound fertilizer.

(2) synthetic materials are plastics, synthetic fibers, synthetic rubber, etc., to give an example can be, such as plastic film.

The answer is:

(1) ammonium dihydrogen phosphate;

(2) plastic film and so on.