1. There must be two large sinks in which the pots may be completely immersed. The water in one sink should be capable of being raised to boiling-point.
2. All dirty pans should be well soaked for a few minutes in boiling water to which a little soda has been added.
3. They should be well scoured, using either a brush or wire wool or similar agent with a scouring powder.
4. The pans are then rinsed in clean hot water and placed upside down to dry.
5. The copper surfaces, if tarnished, may be cleaned with a paste made from 1/3 silver sand, 1/3 flour mixed with vinegar; the pans are then thoroughly rinsed and dried.
![What is the percentage by mass of copper in copper in copper (l) oxide (CU2O)? [O = 16; CU =64] past-questions-and-answers](https://erudites.ng/wp-content/uploads/2020/06/past-questions-and-answers-150x150.jpg)

