A teacher investigates the reactions of copper carbonate, CuCO3\text{CuCO}_3CuCO3.
The diagram shows the reactions the teacher does.
![A flowchart showing the chemical reactions of copper carbonate:
State the name of the soluble salt, X.
State the name of gas Y.
Gas Z relights a glowing splint. State the name of gas Z.
The teacher performs a flame test of the copper metal. What colour flame does the teacher observe?
Lead metal is extracted from lead(II) oxide by heating with carbon as shown in the word equation:
lead oxide+carbon→lead+carbon dioxide\text{lead oxide} + \text{carbon} \rightarrow \text{lead} + \text{carbon dioxide}lead oxide+carbon→lead+carbon dioxide
Explain why lead is extracted. Use ideas about the reactivity series.
Metals are often mixed with other elements to make alloys. The table gives information about some common alloys.
| Alloy | Main elements | Uses |
|---|---|---|
| solder | lead and ........................ | joining electrical components |
| stainless steel | iron, chromium and ........................ | cutlery |
| mild steel | iron and carbon | ........................ |
Complete the table.