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.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Is sand soluble or insoluble?

1/5

Q2.Is salt soluble or insoluble?

2/5

Q3.When should you use filtration?

3/5

Q4.When should you use evaporation?

4/5

Q5.When should you use sieving?

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Is sand soluble or insoluble?

1/5

Q2.Is salt soluble or insoluble?

2/5

Q3.When should you use filtration?

3/5

Q4.When should you use evaporation?

4/5

Q5.When should you use sieving?

5/5

Video

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

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

How can we tell a chemical reaction has taken place?

Don't worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Which indicator of a chemical change is represented by the picture above?
Flasks

1/5

Q2.Which indicator of a chemical change is represented the picture above?
Nose

2/5

Q3.Which indicator of a chemical change is represented by the picture above?
Thermometers

3/5

Q4.Which indicator of a chemical change is represented the picture above?
Experiment with chemical change

4/5

Q5.Which indicator of a chemical change is represented the picture above?
Experiment with chemical change

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

How can we tell a chemical reaction has taken place?

Don't worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Which indicator of a chemical change is represented by the picture above?
Flasks

1/5

Q2.Which indicator of a chemical change is represented the picture above?
Nose

2/5

Q3.Which indicator of a chemical change is represented by the picture above?
Thermometers

3/5

Q4.Which indicator of a chemical change is represented the picture above?
Experiment with chemical change

4/5

Q5.Which indicator of a chemical change is represented the picture above?
Experiment with chemical change

5/5

Lesson summary: How can we tell a chemical reaction has taken place?

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Time to move!

Did you know that exercise helps your concentration and ability to learn?

For 5 mins...

Move around:
Climb stairs

On the spot:
Dance