Practical questions
You will complete 21 required practical activities if you are studying GCSE combined science: Trilogy. You could be asked questions about the apparatus, methods, safety precautions, results, analysis and evaluation of these experiments.
There are no required practical activities in the atomic structure and periodic table section. However, there may be some questions drawing on practical skills relating to this topic within other questions on the paper.
These questions have been written by Bitesize consultants as suggestions to the types of questions that may appear in an exam paper.
Sample question 1
Question
Two students are investigating the growth of seedlings in different nutrient solutions.
What safety precautions should they take? [2 marks]
Two from:
- The should wear safety googles [1] and tie their hair back if it is long [1].
- They should work standing up [1] and wash their hands after the experiment is finished [1].
Sample question 2
Question
Describe the method you would use to investigate the growth of seedlings in different nutrient solutions. [6 marks]
Answer (six from):
- Sow ten barley seeds onto cotton wool in two different petri dishes [1].
- Add 10 cm3 of distilled water, seal using tape and place on a sunny windowsill to germinate [1].
- About one week after germination, open the petri dish, pour out any distilled water and add a fertiliser solution to one petri dish [1].
- Add the same volume of water to the other petri dish of seedlings [1].
- Replace both petri dishes on the window sill and leave for two weeks [1].
- Open each petri dish and carefully remove each seedling from the cotton wool [1].
- Dry in an oven and record the total dry mass of each set of ten seedlings [1].
Sample question 3
Question
The mean growth of seedlings in four different test solutions are shown in the table below.
| Solution added | Mean growth (cm) |
| Distilled water | 3.5 |
| Magnesium sulfate and potassium nitrate | 5.8 |
| Magnesium sulfate (deficient in nitrogen) | 4.3 |
| Potassium nitrate (deficient in magnesium) | 3.5 |
| Solution added | Distilled water |
|---|---|
| Mean growth (cm) | 3.5 |
| Solution added | Magnesium sulfate and potassium nitrate |
|---|---|
| Mean growth (cm) | 5.8 |
| Solution added | Magnesium sulfate (deficient in nitrogen) |
|---|---|
| Mean growth (cm) | 4.3 |
| Solution added | Potassium nitrate (deficient in magnesium) |
|---|---|
| Mean growth (cm) | 3.5 |
Two students looked at these results. What conclusions can they draw from them? Use numbers in your answer. [4 marks]
The mean growth of seedlings is the same at 3.5 cm for both distilled water and potassium nitrate [2]. Seedlings grown in magnesium sulfate grew more than either of these with a mean of 4.3 cm [1]. The greatest mean growth was 5.8 cm and this was in seedlings grown in both magnesium sulfate and potassium nitrate [1].
If an exam question says 'use numbers or data in your answer' you will normally get one mark for saying what is happening and another mark for using the correct number. In the question above, the first line of the answer is 'The mean growth of seedlings is the same at 3.5 cm for both distilled water and potassium nitrate [2].' The first mark is for saying the mean growth is the same and the second mark is for using the correct number (3.5 cm)
