With the majority of students being asked to stay at home now, we thought it would be useful to put together some fun and easy home science experiments… starting with this density experiment!
Three empty jars
One tall glass or jar
A small measuring jug
100ml golden syrup
100ml sunflower or cooking oil
Some food colouring
Lots of small objects. Examples:- piece of Lego, small piece of wood, a metal screw, coin, pebble – anything that can be easily washed.
You could also try this with honey or washing up liquid.
Weigh the first jar and write down the result. Measure out 100ml of golden syrup and pour into this jar. (It is a bit easier to do this of the syrup is a little warm).
Weigh the jar again with the golden syrup in it and record this weight. Take away the first weight from the second weight and this will tell you how much the golden syrup weighs.
Repeat step 1 with oil.
Repeat step 1 with water and add a few drops of food colouring.
Compare the weight of 100ml of syrup, oil and water. Do they all weigh the same?
Pour each liquid into the bigger jar. What happens?
Each of the layers will be a separate liquid. This is because the densest liquid has gone to the bottom, the least dense liquid has floated on the top. How does this compare to the weight of each liquid?
Now, take your first object. Predict which layer you think it will float on. Try it and see if you are correct. Interestingly, some things that seem light will sink and things that seem heavy will float.
The science behind this experiment is all about density.
Everything is made up of molecules. If these molecules are packed tightly together in an object, then that object is dense. If the molecules are further away from each other, then that object is less dense. This is the same for a liquid.
Objects or liquids float on liquids that have a higher density.
The plastic counter will sink through the oil but float on the water; the coin will sink through both; therefore, the coin is denser than the plastic counter and it is also denser than the oil and the water.