Carry out the transformations according to the scheme: HCL – KClO3 – P2O5 – H3PO4 – KH2PO4

1) In order to obtain potassium chlorate from hydrochloric acid, two reactions are required. Initially, hydrochloric acid reacts with mangan (IV) oxide, resulting in mangan (II) chloride, chlorine and water:

4HCl + MnO2 → MnCl2 + Cl2 + 2H2O;

Then chlorine reacts with potassium hydroxide and now it turns out – potassium chlorate, potassium chloride and water:

3Cl2 + 6KOH → KClO3 + 5KCl + 3H2O;

2) Potassium chlorate reacts with pure phosphorus and forms hydrochloric acid and phosphorus (V) oxide:

5KClO3 + 6P → HCl + 3P2O5;

3) Phosphorus (V) oxide reacts with water, in the process of the connecting reaction, phosphate acid is obtained:

P2O5 + 3H2O → 2H3PO4;

4) As a result of the interaction of phosphate acid with potassium hydroxide, potassium dihydrogen phosphate and water are formed:

2H3PO4 + 2KOH → 2KH2PO4 + 2H2O.