This question is about the extraction of metals.
When zinc oxide is heated with carbon, zinc is made.
(i) Complete the word equation for this reaction.
zinc oxide+carbon→…………………………+………………………… \text{zinc oxide} + \text{carbon} \rightarrow \text{\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots} + \text{\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots} zinc oxide+carbon→…………………………+…………………………(ii) Zinc oxide is reduced during this reaction.
Explain how you can tell that zinc oxide is reduced.
Look at the reactivity series of some metals. Carbon is also included.
(i) Zinc is usually extracted from zinc oxide by heating zinc oxide with carbon.
Explain why. Use the reactivity series to help you.
(ii) Sodium is extracted from sodium chloride by electrolysis.
Explain why. Use the reactivity series to help you.
The table shows some information about titanium and silver.
| Metal | Cost of 1 kg (£) | Amount in Earth's crust (%) |
|---|---|---|
| Titanium | 4.50 | 0.56 |
| Silver | 620.00 | 0.0000075 |
Suggest two reasons why it could be more important to recycle silver than titanium. Use information from the table to help you.
Brass is an alloy often used to make musical instruments and decorative items.
A sample of a brass alloy contains 4.32 g4.32\text{ g}4.32 g of zinc and 12.18 g12.18\text{ g}12.18 g of copper only.
Calculate the percentage of zinc in this alloy.
Give your answer to 3 significant figures.
81 exam-style questions on OCR GCSE Chemistry Improving processes and products. Each one has a worked solution and a mark scheme showing where the marks go.