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 practise 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

Listen to the full series on BBC Sounds.

To play this video you need to enable JavaScript in your browser.

This video can not be played

Dr Alex Lathbridge answers questions about practicals.

Open Transcript

Sample question 1 - Foundation

Question

Describe how you could test for the presence of chlorine gas. [1 mark]

Sample question 2 - Foundation

Question

Fiona investigates the reactivity of magnesium, zinc and iron by measuring the energy change of their displacement reaction with copper sulfate solution.

She adds 10 cm³ of copper sulfate solution to a polystyrene beaker and measures the initial temperature.

She then adds one gram of metal and measures the maximum temperature reached.

a) State two variables that Fiona should control. [2 marks]

b) Calculate the temperature change for each metal. [1 mark]

Metal	Initial temperature	Final temperature	Temperature change
Zinc	20°C	28°C
Iron	20°C	23°C
Magnesium	20°C	34°C

Metal	Zinc
Initial temperature	20°C
Final temperature	28°C
Temperature change

Metal	Iron
Initial temperature	20°C
Final temperature	23°C
Temperature change

Metal	Magnesium
Initial temperature	20°C
Final temperature	34°C
Temperature change

c) Draw a graph of the result. [3 marks]

d) State which metal is most reactive and explain how this is shown by the results. [2 marks]

a) Any two from:

concentration of copper sulfate solution
volume of copper sulfate solution
surface area of metal (eg powder or single piece)
number of moles of metal added (accept mass)
initial temperature of the solution

[2]

b)

Metal	Initial temperature	Final temperature	Temperature change
Zinc	20°C	28°C	8°C
Iron	20°C	23°C	3°C
Magnesium	20°C	34°C	14°C

Metal	Zinc
Initial temperature	20°C
Final temperature	28°C
Temperature change	8°C

Metal	Iron
Initial temperature	20°C
Final temperature	23°C
Temperature change	3°C

Metal	Magnesium
Initial temperature	20°C
Final temperature	34°C
Temperature change	14°C

c) Marks awarded for:

bar graph plotted [1]
three bars of correct height [1]
axes correctly labelled [1]

Bar graph of temperature change of three metals

d) Magnesium is most reactive [1]. The results show that its displacement reaction was most exothermic/released the most energy [1].

Sample exam questions - air and water - OCR 21st CenturyPractical questions