Two reactions were carried out in open flasks standing on balances. In reaction X, zinc was added to dilute hydrochloric acid. In reaction Y, zinc oxide was added to dilute hydrochloric acid. Which statement describes the balance readings?
The reading falls in X and stays the same in Y.
The reading falls in X and also falls in Y.
The reading stays the same in X and falls in Y.
The reading stays the same in both X and Y.
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.