Write the reaction equation: Ca → CaO → Ca (OH) 2 → Ca3 (PO4) 2 Cu → CuO → CuCl2 → Cu (OH) 2 → CuO → Cu

2Ca + О2 = 2CaO – calcium is oxidized by oxygen, forming calcium oxide.
CaO + H2O = Ca (OH) 2 – calcium oxide reacts with water to form calcium hydroxide.
3Ca (OH) 2 + Н3PO4 = Ca3 (PO4) 2 + 3Н2О – calcium hydroxide reacts with phosphoric acid, forming calcium orthophosphate and water.
2Cu + О2 = 2CuO – oxidized by oxygen, copper forms its oxide.
CuO + 2HCl = CuCl2 + H2O – copper oxide reacts with hydrochloric acid, forming copper chloride and water.
CuCl2 + Н2О = Cu (OH) 2 + НCl – copper chloride reacts with water, forming copper hydroxide and hydrochloric acid.
Cu (OH) 2 → CuO + H2O – copper hydroxide decomposes, forming copper oxide and water.
CuO + 2K = Cu + K2O – copper oxide reacts with potassium to form copper and potassium oxide.