Write the reaction equations: K2S – K2O – K (OH) – K2SO3 – K2O.

Let us write down the solution of the transformation chain for inorganic substances:

Potassium sulphide – potassium oxide – potassium hydroxide – potassium sulphide – potassium oxide

2K2S + SO2 = 2K2O + 3S – OBP, occurs when heated, potassium oxide is obtained;
K2O + H2O = 2KOH – compounds, potassium hydroxide was formed;
2KOH + H2SO3 = K2SO3 + 2H2O – ion exchange, potassium sulphide is released;
K2SO3 = K2O + SO2 – decomposition, potassium oxide obtained.
The solution process confirms the connection of salts, oxides, bases.