Study Hub

Study Guides

This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.

Back to Study HubBrowse Year 7 Science Guides

Year 7 - Science

Changes of state: energy and evaporation

Solid, liquid, gas states and changes of state

Unit Summary

This unit covers the properties of solids, liquids, and gases using the particle model, including gas pressure. It explains changes of state in terms of the particle model while developing skills in using appropriate techniques, apparatus, and materials in lab work.

Lesson Summary

You will learn to describe and explain what happens when a substance changes state and how evaporation occurs.

Key Notes

  • States of matter can have differing amounts of energy.
  • Solid states have the least energy, gas states have the most energy.
  • A substance in its liquid state can evaporate at temperatures below its boiling point.
  • The hotter the water, the more quickly it evaporates.
  • Water evaporates at temperatures that are lower than 100℃.

Vocabulary To Learn

  • energy: Particles gain or lose energy when a substance changes state.
  • evaporation: When a particle of a substance in the liquid state at the surface, has enough energy to change to the gas state and mix with air.
  • evaporation rate: The evaporation rate is a measure of how quickly a substance evaporates.
  • alcohol: Ethanol is a type of alcohol that has a higher evaporation rate than water.

Common Mistakes To Avoid

  • Evaporation only occurs above the boiling point of a substance.

3 Quick Questions (With Answers)

1. Explain the scientific idea in this lesson using two key points.

States of matter can have differing amounts of energy. Solid states have the least energy, gas states have the most energy.

2. Define this scientific word and use it in context. 'energy'

Particles gain or lose energy when a substance changes state. Include the word in a full scientific explanation, not as a single label.

3. Correct this common scientific misunderstanding.

Mistake: Evaporation only occurs above the boiling point of a substance. Correction: Give examples of substances other than water.

More Lessons In This Unit

Browse all guides in the Year 7 Science guide library.