Calcium carbonate reacts with dilute hydrochloric acid in an open flask on a balance. The balance reading falls by 0.44 g in the first 3 minutes and then stays constant. Which statement best explains these results?
Carbon dioxide particles are destroyed as the reaction takes place.
Carbon dioxide leaves the flask, and after 3 minutes no more is made.
Calcium carbonate dissolves, so its mass is no longer on the balance.
Hydrochloric acid evaporates from the flask while the reaction happens.
40 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.