We are currently developing activities that we will share with primary schools through events organised by the Wider Participation team at the University of Liverpool. We also plan to visit schools in Cheshire. The activities are designed to inspire new generations of scientists and engineers and to challenge emerging stereotypes and biases in young children.
Children will learn about complex fluids and their properties, as well as other scientific concepts (for example density and surface tension) through fun, colourful and safe experiments. We use ingredients that you may already have in your kitchen cupboards!
If you are a primary school interested in our outreach activities please do get in touch through the contact form.
Colourful Experiments that you can do at home
This is how my 7yo son called this experiment! Children can learn about density, miscibility, and hydrophilicity in this experiment.
What do you need? Just water, vegetable oil, and your favourite selection of concentrated (must be water based) food colourings.
Follow these steps: 1) Pour ~100mL of oil and add a few drops of each colour. Food colouring is water based, so the droplets will not mix in the oil and will sit at the bottom due to the density difference. 2) Pour 300 mL of water in a tall jar. Vigorously stir the oil with the food colourings as fast as you can, and 3) quickly pour it on top of the water. 4) Observe what happens and enjoy!
Shaking or vigorously stirring the oil with colours, creates very small droplets of food colouring droplets in the oil. When these tiny droplets sit at the interface between oil and water, they difuse into the water forming a very colourful ‘rain’ effect.
SURFACTANT PATTERNS ON DILUTED CORNSTARCH SUSPENSION
What do you need? Milk (or a diluted suspension of cornstarch in water), food colourings, washing up liquid and a little bit of cotton wool.
Follow these steps: 1) place the milk (or cornstarch suspension) on a shallow bowl. 2) Choose some food colourings and place a few droplets in the middle of the plate. 3) Take a bit of cotton wool with a few drops of washing up liquid (you may need to make the cotton wool a bit damp). 4) place the cotton wool in the middle of the plate, just above the food colourings. 5) observe and enjoy!
This experiment turns out different every time! try it with different colours and placing the drops on different positions. Share your results with us!
DENSITY AND MISCIBILITY GAME
With this density game, you can play a trick on children and adults!
What do you need? Four small glass vials, two food colourings, warm water and cold water, two small square pieces of plastic or cardboard (separators to prevent mixing before you do the trick!).
Follow these steps: 1) Take the four glass vials and place cold water (at room temperature) in three of them and hot water (the hottest you can from the tap) in the fourth vial. (Note: if children are doing the experiment, make sure that an adult supervises them and checks the water temperature). 2) Add the colours of your choice into the vials, but make sure you have the same colour combination to compare!
For example, here we chose blue and red, but only one of the red mixtures is made with hot water. Test 1: blue in cold water (bottom) and red in cold water (top). Test 2: blue in cold water (bottom) and red in hot water (top).
Step 3) Put the vials with the same colour and at the same temperature on the worktop (blue colour in the video above and images below). 4) Place the separators on top of these two vials. 5) Now, bring the “cold” vial with the second colour (red in the video and images) and carefully place it on top of the separator on the first vial. 6) Remove the separator very carefully and slowly. What happens? And why?
Step 7) Repeat step 5 (on the unused vial that is ready with the separator on top) but this time put on top the second vial with the “hot” solution in a different colour. 8) Repeat step 6. What happens this time? What is the difference between them?