Reporter Ellie Constantine has some easy ways to whip up some fun and fill some hours on a free day - just peak inside your kitchen cupboards.
• Cornflour slime: See the video
What you need:
Cornflour, as much as you can.
Water
A bowl
Food colouring if desired
What to do:
- Put most of the cornflour in the bowl
- Add water to the cornflour until it starts behaving strangely - you will want at least twice as much cornflour as water, so don't add it too fast.
- Try moving your hand through the liquid slowly, then fast, have a play with it.
- When you move slowly it will flow slowly, but if you try and change its shape quickly it goes hard. If you get the consitancy right, you can even roll a ball out of it that will bounce, then when it stops, flow as a liquid again.
What is happening?:
Cornflour is made up of lots of tiny starch particles, these are very attracted to water so the water gets in amongst them very quickly.
The water acts as a lubricant, so when you move it slowly the particles have time to move past each other and they can flow like a liquid.
However if you apply a rapid force it causes the particles to move slightly causing the particles that are almost touching to jam together.
Now instead of having lots of lubricated individual particles you have a solid structure of lumps touching each other which can't flow.
• Frothy: See the video
What you need:
1tbsp of baking soda
1tbsp of laundry detergent
About 3/4 cup of water
About 1/4 cup of vinegar
Several drops of food coloring (optional)
A 400ml glass
A waterproof tray
What to do:
- Place the drinking glass on the tray and add the baking soda and detergent to the glass.
- Add 180ml of water and a few drops of optional food coloring and stir.
- Quickly pour the vinegar into the glass. The mixture will foam up and over the top of the glass, covering the tray with a froth of tiny bubbles.
What is happening?:
In this experiment, the fizz is produced by a chemical reaction between baking soda and vinegar. Baking soda and vinegar react, and one of the products of the reaction is carbon dioxide gas. This gas forms bubbles that are surrounded by the liquid. The laundry detergent makes the bubbles last longer. The volume of the gas produced and trapped in the foam is much greater than the glass can hold, so some of it spills over the top of the glass.
