Practical questions
You will complete 21 required practical activities if you are studying GCSE combined science: Synergy. You could be asked questions about the apparatus, methods, safety precautions, results, analysis and evaluation of these experiments.
There will be a number of different types of practical based questions. Some will be on the set required practicals, some will cover the working scientifically terms and some will be on other science practicals which you might have done in class. Use all the information given in the question particularly any diagrams to help you understand what the question is about.
This page contains AQA material which is reproduced by permission of AQA.
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Dr Alex Lathbridge answers questions about practicals.
Sample question 1 - Foundation
Question
A student used the apparatus shown below to compare the energy needed to heat blocks of different materials.
Each block had the same mass.
Each block had holes for the thermometer and the immersion heater.
Each block had a starting temperature of 20°C.
The student measured the time taken to increase the temperature of each material by 5°C.
State two variables the student controlled. [2 marks]
Any two from:
- mass (of block) [1]
- starting temperature [1]
- final / increase in temperature [1]
- voltage / pd [1]
- power (supplied to each block) [1]
- type / thickness of insulation [1]
Sample question 2 - Foundation
Question
Crude oil is a mixture of a very large number of compounds.
The image shows a laboratory experiment to separate crude oil.
Use the correct word from the box to complete each sentence.
| Condensation | Decomposition | Distillation | Evaporation | Reduction |
| Condensation |
| Decomposition |
| Distillation |
| Evaporation |
| Reduction |
The process of separating crude oil is fractional ______. [1 mark]
The process taking place at A is ______. [1 mark]
The process taking place at B is ______. [1 mark]
The process of separating crude oil is fractional distillation.
The process taking place at A is evaporation.
The process taking place at B is condensation.
Sample question 3 - Higher
Question
A group of students investigated the energy released by the combustion of four hydrocarbon fuels.
The image shows the apparatus used.
Each hydrocarbon was burned for two minutes and the temperature increase of the water was measured.
Suggest one improvement to the apparatus, or to the use of the apparatus, that would make the temperature increase of the water for each fuel more accurate.
Give a reason why this is an improvement. [2 marks]
Use a lid or draught shield [1].
Reduce energy / heat loss [1].
Sample question 4 - Higher
Question
A group of students investigated the energy released by the combustion of four hydrocarbon fuels.
The image shows the apparatus used.
Each hydrocarbon was burned for two minutes.
The table shows the students' results.
| Name and formula of hydrocarbon fuel | Mass of fuel used in g | Temperature increase of water in °C | Energy released by fuel in kJ | Energy released by 1.0 g of fuel in kJ | Relative amount of smoke in the flame |
| Hexane (C6H14) | 0.81 | 40 | 16.80 | 20.74 | Very little smoke |
| Octane (C8H18) | 1.10 | 54 | 22.68 | 20.64 | Some smoke |
| Decane (C10H22) | 1.20 | 58 | 24.36 | 20.30 | Smoky |
| Dodecane (C12H26) | 1.41 | 67 | 28.14 | 19.96 | Very smoky |
| Name and formula of hydrocarbon fuel | Hexane (C6H14) |
|---|---|
| Mass of fuel used in g | 0.81 |
| Temperature increase of water in °C | 40 |
| Energy released by fuel in kJ | 16.80 |
| Energy released by 1.0 g of fuel in kJ | 20.74 |
| Relative amount of smoke in the flame | Very little smoke |
| Name and formula of hydrocarbon fuel | Octane (C8H18) |
|---|---|
| Mass of fuel used in g | 1.10 |
| Temperature increase of water in °C | 54 |
| Energy released by fuel in kJ | 22.68 |
| Energy released by 1.0 g of fuel in kJ | 20.64 |
| Relative amount of smoke in the flame | Some smoke |
| Name and formula of hydrocarbon fuel | Decane (C10H22) |
|---|---|
| Mass of fuel used in g | 1.20 |
| Temperature increase of water in °C | 58 |
| Energy released by fuel in kJ | 24.36 |
| Energy released by 1.0 g of fuel in kJ | 20.30 |
| Relative amount of smoke in the flame | Smoky |
| Name and formula of hydrocarbon fuel | Dodecane (C12H26) |
|---|---|
| Mass of fuel used in g | 1.41 |
| Temperature increase of water in °C | 67 |
| Energy released by fuel in kJ | 28.14 |
| Energy released by 1.0 g of fuel in kJ | 19.96 |
| Relative amount of smoke in the flame | Very smoky |
A student concluded that hexane is the best of the four fuels.
Give two reasons why the results in the table support this conclusion. [2 marks]
Hexane gives out the greatest energy (per 1.0 g) [1].
Hexane produces the least smoke [1].
