Simply Science Time For Experiments!
By Shani Asokan Ceylon Today Features
Science doesn’t have to be difficult. It can be simple, fun and a great stay at home activity! Here are some simple experiments you can do with a few materials you have lying around the house.
While these experiments are safe to do at home, we recommend getting an adult to help you. Besides, this is fun for the whole family. Get ready to see science in action!
Do you like playing secret agent? Hunting down clues and cracking codes? Well here’s a way to elevate your game. Here’s a way to write secret messages in invisible ink!
What you will need:
- Lemon juice
- Small bowl
- Cotton buds/Q-tips
- White paper (A4 or anything you have)
- Hair dryer
Create your ink
Pour the lemon juice into a bowl (you don’t need much, a tablespoon or two should do the trick). Dip the cotton bud into a bowl and use it to write out your message.
Dip the cotton bud into the lemon juice as many times as you need to write out your message.
As you write, you will see the message dry up and soak into the paper until none of it is visible.
Once the paper is dry, hold the hair dryer to the paper, letting the warm air blow on to the message. Watch your message appear!
How does it work?
So why does this work? When you expose lemon juice to heat, it decomposes and releases carbon. When carbon comes into contact with the oxygen in the air, a process of oxidation begins and allows the message to show up on the paper.
This process is similar to something that you may have already seen. Often, when you cut up an apple and leave it on a plate for too long, you will notice that the apple turns brown. This is due to the same process of oxidation. Similarly, this is the same process that causes objects made of iron to become rusty when left outside for too long.
Did you know that you can create crystals with just a handful of ingredients? This type of crystal, geodes as they are called, are usually formed in igneous or sedimentary rock types. Here’s how you can make some at home.
What you will need:
- Clean eggshells
- Table salt
- Rock salt
- Epsom salt
- Coffee cups or small heat proof containers
- Food colouring
- Paper muffin cups or egg cartons
Create your geodes
When cracking your eggs, make sure you crack them as close the narrow end as possible, so that you have a cup shape. Ask an adult to help you do this.
Wash the shells in hot water. This will help you pull out the skin-like membrane inside the shell. It is important that you get all the membrane out to avoid any mould from forming.
Put each eggshell in a muffin cup or individually cut out egg carton to hold them upright.
Ask an adult to help you heat up some water until it is boiling and fill your heat proof container until it is half full. Add your salts and sugar to the water, enough to make up quarter of the container. So if you add half a cup of water, you should add a quarter cup of the salts and sugar.
Stir the mixture. Once the solids have dissolved, keep adding more until the solids will no longer dissolve in the water. This means that the water has reached maximum saturation. Add food colouring
Carefully fill your eggshells with your mixture. Filling as much as possible without letting them overflow or tip over.
Leave the eggshells in a safe place until all the water evaporates and the crystals form
How it works
When you add enough salts and sugars to your water, it creates a super saturated solution. This means that the solids took advantage of the energy in the hot water to dissolve until there is no more space between the molecules in the solution.
As the solution cools, the water loses its energy and crystals (salt and sugar) form again. But this time, as the water evaporates, the crystals are allowed to become bigger than they were in their salt and sugar form.
This process is similar to the way geodes are formed in rock formations.