New
New
Year 10
AQA
Higher

Energy changes: displacement practical

I can complete a practical to measure the temperature change in a displacement reaction, record results, analyse data, and write a conclusion.

New
New
Year 10
AQA
Higher

Energy changes: displacement practical

I can complete a practical to measure the temperature change in a displacement reaction, record results, analyse data, and write a conclusion.

Lesson details

Key learning points

  1. Displacement reactions involve a more reactive element replacing another in a compound.
  2. Exothermic reactions release energy to the surroundings, often through heating.
  3. The initial and final temperatures of the reaction mixture need to be recorded to calculate energy change.
  4. Hypotheses guide predictions about the effect of variables in experiments.
  5. Bar charts can visually represent collected results to help analyse data.

Common misconception

Pupils often measure the final temperature of the reaction mixture rather than the highest temperature.

Encourage pupils to keep monitoring the temperature until it starts to decrease; that way they will know they have seen the highest temperature.

Keywords

  • Displacement - The more reactive element takes the place of a less reactive element in a compound.

  • Exothermic - Exothermic chemical reaction is a type of reaction in which energy is transferred from the reaction to the surroundings e.g. combustion.

  • Hypothesis - A prediction that is supported with an explanation.

  • Conclusion - Sums up what has been found out during the investigation. It always refers to both the independent and dependent variables.

  • Bar chart - A chart showing solid columns; to present data usually used when one variable is discrete.

Ask pupils to suggest how they would improve the investigation if they had to do it again. They may need scaffolding to help them consider aspects of the equipment and how to obtain more reliable data.
Teacher tip

Equipment

A selection of metals as fine particles, a metal salt solution, polystyrene or insulated cups with lids, thermometers, balances and measuring cylinders.

Licence

This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

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6 Questions

Q1.
Which element is more reactive, magnesium or copper?
Both are equally reactive
Copper
Correct answer: Magnesium
Neither is reactive
Q2.
Which type of data is best represented by a bar chart?
Continuous data
Correct answer: Discrete data
Variable data
Textual data
Q3.
What is a hypothesis in an experiment?
A conclusion drawn from results
An observation made during the experiment
Correct answer: A prediction with an explanation
A proven theory
Q4.
What is an independent variable in an experiment?
Correct answer: The variable that is changed
The variable that is measured
The variable that stays constant
The variable that is dependent on other factors
Q5.
What is a dependent variable in an experiment?
The variable that is changed
Correct answer: The variable that is measured
The variable that stays constant
The variable that affects the results
Q6.
Why is it important to control variables in an experiment?
Correct answer: To ensure the results are reliable and valid
To increase the number of variables
To make the experiment faster
To introduce random factors

6 Questions

Q1.
What occurs during a displacement reaction?
Correct answer: A more reactive element replaces a less reactive one
A less reactive element replaces a more reactive one
No reaction occurs
The reaction involves no change in the elements
Q2.
What do exothermic reactions release?
Correct Answer: energy
Q3.
What does an exothermic reaction typically result in?
Decrease in temperature
Correct answer: Increase in temperature
No temperature change
Decrease in pressure
Q4.
How do you calculate the energy change in a reaction?
Subtract initial mass from final mass
Correct answer: Subtract initial temperature from final temperature
Subtract initial volume from final volume
Subtract mass from volume
Q5.
Which substance would be displaced if zinc is added to copper sulfate solution?
Correct answer: Copper
Sulfur
Zinc
No reaction would occur
Q6.
What is the correct symbol equation for the displacement reaction of zinc with copper sulfate?
Zn + CuSO₄ → ZnCu + SO₄
Zn + CuSO₄ → ZnCuSO₄
Correct answer: Zn + CuSO₄ → ZnSO₄ + Cu