A student measured the concentration of a copper sulfate solution several times using the same method. After leaving out an anomalous result, the student estimated the uncertainty in the mean concentration as ±0.02 mol/dm3\pm 0.02\ \text{mol/dm}^3±0.02 mol/dm3.
Which statement about the range of the valid results is correct?
The range was 0.01 mol/dm30.01\ \text{mol/dm}^30.01 mol/dm3, because the range is half of the uncertainty.
The range cannot be found, because the mean concentration is not given.
The range was 0.02 mol/dm30.02\ \text{mol/dm}^30.02 mol/dm3, because the uncertainty is equal to the range.
The range was 0.04 mol/dm30.04\ \text{mol/dm}^30.04 mol/dm3, because the uncertainty is half of the range.
95 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.