Make states of matter charts – quilling for older children, sticky dots for younger ones.
I encouraged the children to draw three bowls and write the words ‘Solid, Liquid, Gas’ next to them. Then the older children quilled round shapes and the younger children stuck round stickers, to represent molecules within the different states. Some of their efforts were more accurate than others, so this was a great starting point for discussion around states of matter.
Today, we’re talking about states of matter. The four most common ones are solid, liquid, gas and plasma.
We’re going to start with a game to try and identify the state of matter of various objects that I’ve brought with me.
Show the children water, ice and air.
Then show the children a plasma ball.
Plasma is an unusual state of matter. It is almost a gas, but it has been heated or electrically charged to change the number of electrons it has. This makes it behave in an unusual way. You can clearly see the filaments. Like a gas, plasma fills the container it is in and doesn’t keep a definite shape. Plasma – unlike most gases – is highly conductive of electricity, and reacts to magnetic fields.
Does the plasma remind you of anything in nature? Lightning is a plasma that you see quite often.
Give the children venn diagram pictures with solid, liquid and gas circles overlapping. Hand out little pictures for them to stick in the right circles. StatesofMatterSortingActivity
Solid – Red, Liquid – Blue, Gas – Yellow.
Show the items in the table below, talk about what they might be. As you name each one, hand out pictures for the children to add to the overlapping portions of their venn diagrams.
|Substance||Name||Stuff mixed up||Colour|
|Toothpaste||Gel||Liquid in a solid||Purple|
|Styrofoam||Solid foam||Gas in a solid||Orange|
|Ink||Liquid sol||Solid in a liquid||Purple|
|Shaving Cream||Liquid foam||Gas in a liquid||Green|
|Smoke||Solid aerosol||Solid in a gas||Orange|
|Body Spray||Liquid aerosol||Liquid in a gas||Green|
As you have probably seen, it is possible to make substances change their state. Does anyone know what it’s called when a gas turns into a liquid? It’s condensation. It can happen when a gas cools down.
Does anyone know what it’s called when a liquid turns into a gas? It’s evaporation, it can happen when a liquid is heated up.
We can also make gases into liquids by putting them under lots of pressure – that means squeezing them very hard together. The gas in a bottle of fizzy drink remains in liquid form because it is under a lot of pressure, as soon as we release some of the pressure, by opening the bottle, it turns into a gas again.
Open a bottle of fizzy drink and put a balloon over the top, let the children watch the gas collect in the balloon.
Break for drink and snack.
Show the children a wooden skewer and ask what would happen if I put it in boiling water. Stir the boiling water with the skewer to test their theory.
Then do the same with a rod of ice.
Finally, show the children the gallium rod and ask what will happen if I put it in boiling water.
(I wanted to make a spoon, but, my first attempt was very wonky, so, short of time, I went with a rod instead. I made this by melting the gallium in a bain marie and pouring it into a straw.)
Most metals do not do that. Does anyone know what it’s called when a solid turns into a liquid? It’s melting.
This metal has an unusually low melting point.
Do you know anything else with a similar melting point?
Beeswax 620C, Coconut oil 250C, Gallium 300C, Chocolate 300C.
We’re going to melt beeswax and coconut oil, so that we can mix them together to make lip salve.
Pass around coconut oil and beeswax. The children should put one tablespoon of beeswax pellets and two tablespoons of coconut oil in a plastic sandwich bag. They can then place the bag in a cup of boiling water and watch the wax and oil melt. Encourage the children to predict which will melt first, bearing in mind the different melting points. Once both are melted, they can be thoroughly mixed by squeezing the bag (be careful, it will be hot as it comes out of the water!). Then the lip salve can be squeezed into little pots to take home.