2 Everything we see around us: Matter is…Everything we see around us:Glass MetalPlasticBones Breath
3 Matter can be sorted into three groups: Solid - Like a brickLiquid - Like watergas- Like airGas
4 A solid doesn’t take the shape of a flask So when you put a ball into a flask it doesn’t fill it up or take the shape of the flask - it just stays as a ball in the flask
5 However a liquid does take the shape of a flask but doesn’t fill it up So if we put the same liquid into different containers the liquid changes to be the same shape as the inside of the container but it doesn’t fill it right up
6 A gas takes the shape of a flask and fills it up completely The same is true for air in a room – air will expand to completely fill a room, so we can breath everywhere. If it didn’t we would only be able to breath in certain places in the room where there was air, and we would have to hold our breath in other parts where there wasn’t any air.
7 If we heat most solids we can turn them into liquids For example if we heat a beaker of ice (solid) it turns into a beaker of water (liquid)
8 If we heat most liquids we can turn them into gasses For example boiling Water turns into Steam
9 Also, if we cool most liquids they become solids For example if it’s cold enough rain will turn into snow
10 And if we cool most gasses they become liquids Power stations release hot steam which is cooled by cooling towers and forms rain clouds which return the water back to earth when it rains
11 Gasses are very compressible but liquids and solids are not: For example you can squash a balloon full of gas with your fingers and change it’s shape easily, but you cannot squash a solid ball easily.
12 Some solids are very elastic and extendable (stretchy) For example we can stretch (and bend) a piece of rubber a lot and it comes back to it’s original shape
13 But some solids are not elastic and break easily or stay bent For example if we bend a twig too much it breaks, or if we bend a wire too much it stays bent - which is why we can make wire shapes like stars
14 Some solids conduct heat very well Metal conducts heat very well but cork doesn’t - which is why the wax melts off of the end where it’s attached to the wire, but not off the end where it’s attached to the cork
15 Some Solids Conduct Heat Poorly Which is why we put hot drinks into polystyrene cups rather than glass beakers - to keep them warm and stop us burning our hands!
16 Some materials are also good electrical conductors Which is why we make electrical circuits out of metal wire and not strips of wood or rubber bands!
17 But some materials are not good electrical conductors So if we put cork in the circuit the bulb doesn’t light up. Another bad conductor is plastic which is why we coat electrical wires with plastic - to make them safe to handle!
18 Some materials are harder than others For example chalk and steel can’t cut glass, but diamond can!
19 SummaryWe may not be able to see some types of matter but we can easily see their effects, for example we see a balloon change shape when we fill it with gas, and press on it.We have seen that solids, liquids and gasses can change into each other if we heat them up or cool them downWe have seen that some materials can conduct heat and electricity better than othersAnd finally we have seen that some materials are harder than others, and a harder material can be used to scratch, cut or shape a softer one.