An investigator studied the thermal decomposition of magnesium carbonate.
The word equation for the reaction is:
magnesium carbonate→magnesium oxide+carbon dioxide \text{magnesium carbonate} \rightarrow \text{magnesium oxide} + \text{carbon dioxide} magnesium carbonate→magnesium oxide+carbon dioxideThe experimental procedure was as follows:
The table below shows the results obtained during the investigation:
| Total heating time (minutes) | Mass of crucible and contents (g) |
|---|---|
| 0 | 38.4 |
| 1 | 37.1 |
| 2 | 36.4 |
| 3 | 36.4 |
Determine the mass of the empty crucible.
Explain why the mass of the crucible and its contents decreased during heating.
Suggest why the crucible and its contents were heated until the mass did not change.
When 150 g150\text{ g}150 g of magnesium carbonate is completely decomposed, 178 kJ178\text{ kJ}178 kJ of energy is taken in. The student heated 4.20 g4.20\text{ g}4.20 g of magnesium carbonate until the mass did not change. Calculate the energy taken in during this reaction. Give your answer to 3 significant figures.
What type of reaction takes place when magnesium carbonate is heated?
53 exam-style questions on AQA GCSE Chemistry 3.1 Chemical measurements, conservation of mass and the quantitative interpretation of chemical equations, covering 3.1.1 Conservation of mass and balanced chemical equations, 3.1.2 Relative formula mass, 3.1.3 Mass changes when a reactant or product is a gas, and 3.1.4 Chemical measurements. Each one has a worked solution and a mark scheme showing where the marks go.