Write the reaction equation: P – P2O5 – H3PO4 – Na3PO4– Na2CO3 – CaCO3– CO2 4

1) 4P + 5O2 = 2P2O5 (when phosphorus interacts with oxygen, phosphorus (V) oxide is formed);

2) P2O5 + 3H2O = 2H3PO4 (when phosphorus (V) oxide interacts with water, phosphoric acid is formed);

3) H3PO4 + 3NaOH = Na3PO4 + 3H2O (when phosphoric acid interacts with sodium hydroxide, sodium phosphate and water are formed);

4) 2Na3PO4 + 3H2CO3 = 3Na2CO3 + 2H3PO4 (when sodium phosphate interacts with carbonic acid, sodium carbonate and phosphoric acid are formed);

5) Na2CO3 + CaCl2 = CaCO3 + 2NaCl (when sodium carbonate interacts with calcium chloride, calcium carbonate and sodium chloride are formed);

6) CaCO3 = CaO + CO2 (when heated, calcium carbonate decomposes into calcium oxide and carbon dioxide).