16. Textbook question V

1. What are amphoteric oxides? Give two examples of amphoteric oxides.

 

Metal oxides are basicacidic. However, some metal oxides, such as aluminium oxide, zinc oxide, etc., can act as neutralacidicacidic and basicbasic. Such metal oxides are called amphoteric oxides. They produce salts and carbon dioxidessalts and watersalts and hydrogen gas when they react with acids and bases.

 

2. In the electrolytic refining of a metal $M$, what would you take as the anode, the cathode and the electrolyte?