Study Guides

Unit Summary

This unit covers separating materials using techniques such as filtering and evaporation. It focuses on planning scientific enquiries, recognising and controlling variables, taking accurate measurements, recording complex data, and presenting findings with conclusions, and explanations.

Lesson Summary

You will learn to plan an investigation into the effect of adding salt to ice.

Key Notes

• Rock salt is often stored in a public grit bin and used to melt ice on roads and pavements.
• After being extracted, rock salt usually undergoes processing and crushing before it is transported to grit bins.
• Scientists plan investigations to make comparisons and answer questions.
• Variables can be changed, measured or kept the same in a comparative test.

Vocabulary To Learn

• rock salt: Rock salt is the name given to salt before it is processed.
• grit: Rock salt is a brown colour and looks like gravel, so it is often referred to as grit.
• melt: To melt is to change from a solid state to a liquid state.
• comparative test: In a comparative test, the thing that is being changed has labels, such as the types of materials.
• variable: Variables are the things that can be changed, measured or kept the same in a comparative test.

Common Mistakes To Avoid

• Pupils may think that there is only one type of salt.

3 Quick Questions (With Answers)

More Lessons In This Unit

• Comparing rock salt with table salt (non-statutory) Study Guide
• The effect of adding salt to ice: do and review (non-statutory) Study Guide