Science Week lesson plan: Liquid layers (KS2)

Resources

• Golden syrup
• Washing up liquid
• Water
• Vegetable oil
• Surgical spirit
• Pipettes
• Clear plastic cup
• Small objects such as a coin, dried pea or bean, grape, pen lid and a dice

Show

1. Pour golden syrup into the cup so it is about 1.5 cm deep.
2. Use a pipette to add approximately the same volume of washing up liquid to the cup, on top of the golden syrup.
3. Use a clean pipette to gently add the same volume of water to the top of the washing up liquid.
4. Use a clean pipette to gently add the same volume of vegetable oil to the top of the water.
5. Finally, add a layer of surgical spirit.
6. If any of the layers have mixed, give them time to settle.
7. Drop the small objects into the cup, one-by-one, and observe what happens.

Explain

Density is defined as how much ‘stuff’ is packed into a particular area. A denser object weighs more than the same amount of a less dense object. Liquids that have a higher density, such as syrup, will sink below liquids with a lower density, such as water and oil. Solid objects also range in their densities. They sink into the liquid layers, resting at different levels depending on their density.

Suggest

• What would happen if you mixed the liquids together?
• What other combinations of liquids could you try?
• What would happen if you added the liquids in a different order?

Download PDF

Download a handy PDF version of this lesson plan for you to keep.

Love to Investigate

Love to Investigate is a set of 126 scientific investigations that encourage children to be curious, ask questions and explore the world around them.

Our series of practical, exciting investigations cover tricky topics in new and unusual ways, including evolution, mechanisms and air resistance. All activities come with background knowledge for teachers who haven’t taught the topic before and method boards to help children work more independently.

Love to Investigate is included as part of Curriculum Maestro and Curriculum Maestro Lite (Love to Investigate is no longer sold separately).