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4/3/24
Science Week 2024
Science Week this year is next week, from the 8th to 17th March. Do you have a science week at school? It is most definitely my favourite week of the year! You can find out more about this exciting week on the British Science Week website, where you’ll find lots more information and ideas.
It’s the 30th anniversary of the British Science Week this year and the theme for this year is ‘Time’. You can download an primary activity pack which has loads of fab activities and experiments all based on this idea of time, such as making sundials, water clocks and even biodegradable plastic and lots more.
I’ve thought about 2 fun science experiments that you also might like to do during your Science Week…
Lava Lamp Experiment
What you'll need
Clear tall containers
Water
Oil (clear baby oil or vegetable oil)
Food Colouring
Alka Seltzer Tablets
Experiment
In a clear tall container pour in 1/3 water and add in a couple of drops of food colouring to colour the water. Then add in 2/3 oil on top. Drop in a quarter of an Alka Selzer tablet to your container. It will then start to bubble up and you can watch while it creates a lava lamp effect. You can add the element of ‘time’ to this experiment by warming up the water in one container and having cold water in another. Does that have an impact on the experiment? Test it to find out for yourself!
Conclusion
The oil floats on top of the water as it is lighter than water. The Alka Seltzer tablet reacts with the water and creates the gas carbon dioxide. This makes bubbles in the water as the carbon dioxide rises to the surface as carbon dioxide is lighter than oil and water. When it does this it takes up a tiny bit of the coloured water with it creating the lava lamp effect. Once the bubbles of carbon dioxide reach the surface they burst and then the coloured water sinks back down through the oil, as without the carbon dioxide the water is once again heavier than the oil.
Fruit Powered Clock Experiment
What you'll need
For this experiment you will need to buy a lemon clock, you can buy one here on Amazon.
A lemon or another citrus fruit
Experiment
Attach the red wire on the watch to one of the copper plates. There is a little hole at the top of the copper plate to allow you to do this.
Then attach the black wire on the watch to one of the zinc plates. Again, use the hole at the top of the zinc plate to do this.
Then attach the white wire to the tops of the other copper and zinc plates.
Cut a lemon or other citrus fruit in half.
Put the copper plate attached to the clock in one half of the lemon and the zinc plate attached to the clock in the other half. Then put in the plates attached to the white wire in to each half, making sure there is one copper and one zinc plate in each half of the lemon.
This should power up the watch and it will begin to work.
Conclusion
The copper plates act like the positive electrodes of a battery. They are plated with a metal which is less reactive than zinc. When the plates are inserted into the lemon, a chemical reaction occurs. Electrons move from the zinc plates to the copper plates to form a current, activating the watch. The lemon juice helps conduct electricity. You can replace the lemon with other citrus fruits, a potato, or even use soft drinks and see what effect they have too.
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