How can we tell a chemical reaction has taken place?

In this lesson, we will learn about the difference between physical changes and chemical reactions. We will learn about the particles in both of these types of change and the signs to look out for in a chemical reaction. You will need a pencil, a ruler and a piece of paper for this lesson. If you have baking soda and vinegar then you will need that for an investigation too, but don't worry you can still take part without these things.

Introductory Quiz

This quiz will help you to check any previous learning on this topic, and re-cap anything you may have forgotten. Once you have completed this, click ‘Close Quiz’ and then ‘Next’ below.


Click on the play button to start the video. If your teacher asks you to pause the video and look at the worksheet you should:

  • Click "Close Video"
  • Click "Next" to view the activity

Your video will re-appear on the next page, and will stay paused in the right place.

Final Quiz

This quiz is a great way for you to test your learning from this lesson.

If you would like to re-cap any of the lesson, or repeat any exercise, click ‘Back’ below.

Lesson Complete

You’ve now completed today’s lesson - well done!

If you would like to complete other lessons from your schedule, click ‘Schedule’ below. If you would like to see more lessons from this subject, click ‘Subject’ below.