A student is making a sample of calcium carbonate, CaCO3\text{CaCO}_3CaCO3.
The table gives information about four different methods the student could use.
| Method | Cost of starting materials (£\pounds£) | Mass of CaCO3\text{CaCO}_3CaCO3 produced (g) | Is the CaCO3\text{CaCO}_3CaCO3 pure? |
|---|---|---|---|
| 1 | 10.50 | 5.20 | yes |
| 2 | 9.80 | 14.50 | no |
| 3 | 13.60 | 13.80 | yes |
| 4 | 18.20 | 9.50 | no |
Which method should the student use to make their sample? Explain your answer.
A teacher shows the student how to purify calcium carbonate. If the student knows how to purify calcium carbonate, should they use the same method as they used in part (a)? Explain your answer.
The student reacts the calcium carbonate they have made with hydrochloric acid.
Complete the balanced equation. Include state symbols.
CaCO3(s)+2HCl(aq)→__________(_______)+H2O(l)+__________(_______) \text{CaCO}_3(\text{s}) + 2\text{HCl}(\text{aq}) \rightarrow \text{\_\_\_\_\_\_\_\_\_\_}(\text{\_\_\_\_\_\_\_}) + \text{H}_2\text{O}(\text{l}) + \text{\_\_\_\_\_\_\_\_\_\_}(\text{\_\_\_\_\_\_\_}) CaCO3(s)+2HCl(aq)→__________(_______)+H2O(l)+__________(_______)The student uses 0.3 mol0.3\text{ mol}0.3 mol of hydrochloric acid in the reaction. The hydrochloric acid is the limiting reagent.
At the end of the reaction, 1.15 g1.15\text{ g}1.15 g of calcium carbonate is left unreacted.
Calculate the total mass of calcium carbonate that the student added to the reaction vessel.
Relative atomic masses (ArA_rAr): Ca=40.0\text{Ca} = 40.0Ca=40.0, C=12.0\text{C} = 12.0C=12.0, O=16.0\text{O} = 16.0O=16.0.
91 exam-style questions on OCR GCSE Chemistry Monitoring chemical reactions. Each one has a worked solution and a mark scheme showing where the marks go.