Practical questions
During the GCSE Chemistry course you will complete practical activities from eight Practical Activity Groups (PAGs).
The exams will include questions about some of these experiments. You may also be asked to apply what you know to unfamiliar practical contexts, which will draw on your practical knowledge and understanding.
You could be asked to:
- write or identify a hypothesis or prediction that could be tested in an experiment
- name equipment and measuring instruments, and describe what they do and how they are used
- identify factors that must be controlled, and explain why
- describe how to work safely
- process data by doing calculations and representing them in graphs
- identify patterns and trends in data
- evaluate the accuracy, repeatability and reproducibility of data, and identify possible errors and anomalous results
- suggest improvements to methods
- interpret data and draw conclusions from it
Practical questions will appear throughout both exams papers, and at both Foundation tier and Higher tier. Practical questions could be multiple choice or free response, and could include calculations. A six-mark question could be asked in a practical context, so practice writing in detail about the practical work you have done.
It's important to look back at your lab book or your notes from the practical activities you have done when revising for your exams.
These questions have been written by Bitesize consultants as suggestions to the types of questions that may appear in an exam paper.
Learn about practicals with Dr Alex Lathbridge
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Sample question 1 - Foundation
Question
Describe a practical procedure to prepare crystals of copper sulfate from copper carbonate and sulfuric acid. [5 marks]
The following are valid points that could be included in your answer:
- add copper carbonate powder to sulfuric acid until excess powder is visible [1]
- pour the mixture through a filter paper and funnel [1]
- pour the filtrate (copper sulfate solution) into an evaporating basin [1]
- place on a tripod and gauze and heat with a Bunsen burner until about half the water has evaporated [1]
- allow the remaining water to evaporate [1]
Sample question 2 - Higher
Question
Ethan is investigating how concentration of acid affects its rate of reaction with sodium thiosulfate.
The reaction forms a precipitate so, using a stop clock Ethan times how long it takes for a cross, placed under the conical flask, to disappear.
Describe why his experiment may have poor repeatability. [4 marks]
The following are valid points that could be included in your answer:
- Ethan has to judge by eye when the cross has disappeared [1]
- he may not make this judgement exactly the same each time [1]
- he also has to stop the stop clock when the cross disappears [1]
- his own reaction time could affect this measurement, meaning that it may not be consistent each time [1]