A great time tonight at our annual Science Challenge. This year people had to come up with a device that would launch a ping pong ball into the air and stay airborne for as long as possible. Hmmm! Lots of different designs - not as easy as you'd like to think!
Today we made wonderful marbling patterns with food colouring and milk!
Try this at home!!
Milk (whole )
Food colouring (red, yellow, green, blue)
1. Pour enough milk in the dinner plate to completely cover the bottom to the depth of about 1-2 cm. Allow the milk to settle.
2. Add one drop of each of the four colours of food colouring - red, yellow, blue, and green - to the milk. Keep the drops close together in the centre of the plate of milk.
3. Find a clean cotton bud for the next part of the experiment. Predict what will happen when you touch the tip of the cotton bud to the centre of the milk. It's important not to stir the mix. Just touch it with the tip of the cotton bud. Go ahead and try it. Did anything happen?
4. Now place a drop of dish washing liquid on the other end of the cotton bud Place the soapy end of the cotton bud back in the middle of the milk and hold it there for 10 to 15 seconds. Look at that burst of colour
5. Add another drop of soap to the tip of the cotton bud and try it again. Experiment with placing the cotton bud at different places in the milk. Notice that the colours in the milk continue to move even when the cotton bud is removed. What makes the food colouring in the milk move?
Today's experiment was an endothermic chemical reaction! Check this one out!
bag (15cm x 10cm)
Perform this experiment over a kitchen sink. There is a small chance the zip
lock bag will burst making a wet mess! Zip lock bags of different sizes can be
used, but the quantity of chemicals added will vary. Trial and error will
uncover the correct amount to use to blow the bag up fully.
What to do:
level teaspoon of citric acid in a zip lock bag.
teaspoon of baking soda in the same zip lock bag. And shake the bag gently to
mix the two chemicals.
the measuring cup with cold tap water (about 30ml).
where you have to be quick! Pour the water into the zip lock bag and snap it
Not only does the bag blow up, it also becomes super cold! So don’t forget to
feel its temperature.
try putting about 20ml of vinegar and a flat teaspoon of baking soda into a zip
lock bag and snapping it shut quickly. Compare the difference between this and
the other combination of chemicals.
Why is it so?
Mixing citric acid, baking soda and water together causes a chemical
reaction. The new chemical that is made is carbon dioxide gas. This gas fills
the bag and causes it to blow up. You’ll also notice the bag drops in
temperature as part of the chemical reaction
This week is Primary Science Week and that means loads of Science all week long!
Today we looked at how air moves with an air cannon. Using a bin (clean) with a hole in the bottom and a sheet of plastic tight over the top. Air is forced out by hitting the plastic hard - and can force the air to knock a paper cup off someone's head!
Air can be described as a fluid the way it moves around.
Here's a link to how to make a miniature version of this at home - let us know how you get on!