2. By the end of this lesson you willBy the end of this lesson you will
know:know:
what a ‘material’ iswhat a ‘material’ is
what we mean by ‘property’what we mean by ‘property’
what the properties of solids, liquids andwhat the properties of solids, liquids and
gases aregases are
3. MaterialsMaterials
Everything is made from some sort ofEverything is made from some sort of
‘material’‘material’
Materials are made up of lots and lots ofMaterials are made up of lots and lots of
tiny piecestiny pieces
These tiny pieces are known as particlesThese tiny pieces are known as particles
called moleculescalled molecules
Solids, liquids and gases are all made ofSolids, liquids and gases are all made of
lots of moleculeslots of molecules
4. PropertiesProperties
The property of a material tells usThe property of a material tells us
something about what it is like…something about what it is like…
Materials may be hard, soft, shiny, roughMaterials may be hard, soft, shiny, rough
Can you think of any more?Can you think of any more?
5. SolidsSolids
A solid is something that we can hold onA solid is something that we can hold on
toto
A solid keeps its shape, unless we cut it orA solid keeps its shape, unless we cut it or
shape it ourselvesshape it ourselves
In a solid, all of the particles are packedIn a solid, all of the particles are packed
together very tightlytogether very tightly
6. LiquidsLiquids
Liquids are runnyLiquids are runny
They can be pouredThey can be poured
The particles are less tightlyThe particles are less tightly
packed, so they can move aboutpacked, so they can move about
If poured from one containerIf poured from one container
to another, they will take theto another, they will take the
shape of their new containershape of their new container
7. GasesGases
The particles in gases have lots of room toThe particles in gases have lots of room to
movemove
Gases are all around usGases are all around us
They spread into all of the empty placesThey spread into all of the empty places
they canthey can
Most are invisibleMost are invisible
8. An example – waterAn example – water
Water can be a solid, aWater can be a solid, a
liquid or a gasliquid or a gas
When it is cold it isWhen it is cold it is
solid – ICEsolid – ICE
When it is at roomWhen it is at room
temperature it is atemperature it is a
liquid – WATERliquid – WATER
When it is hot it is aWhen it is hot it is a
gas – STEAMgas – STEAM
9. Your turn!!Your turn!!
Having learned about the properties ofHaving learned about the properties of
solids, liquids and gases I’d like you makesolids, liquids and gases I’d like you make
a list of all of those you know abouta list of all of those you know about
alreadyalready
10. Transitions of States of MatterTransitions of States of Matter
Transition means toTransition means to changechange..
States of matter canStates of matter can transitiontransition into anotherinto another
state by a variety of ways. The four mainstate by a variety of ways. The four main
areare
FreezingFreezing
HeatingHeating
CondensingCondensing
EvaporatingEvaporating
11. FreezingFreezing
When extremely cold temperatures areWhen extremely cold temperatures are
applied to aapplied to a liquidliquid it will turn into a solid.it will turn into a solid.
Freezing `occurs when the molecules of aFreezing `occurs when the molecules of a
liquid slow down enough that theirliquid slow down enough that their
magnetisms cause them to arrangemagnetisms cause them to arrange
themselves into immovable positions as athemselves into immovable positions as a
solid.solid.
For example when we put water in theFor example when we put water in the
freezer, it will turn into ice.freezer, it will turn into ice.
12. MeltingMelting
Melting occurs when heat is applied to aMelting occurs when heat is applied to a
solid and turns it into liquid.solid and turns it into liquid.
When melting, the molecules in the solidWhen melting, the molecules in the solid
begin to relax and move around freely.begin to relax and move around freely.
For example when chocolate is left in theFor example when chocolate is left in the
sun, it will melt into liquid chocolate.sun, it will melt into liquid chocolate.
Similarly ice left on the bench will melt intoSimilarly ice left on the bench will melt into
water.water.
13. EvaporationEvaporation
Evaporation occurs when a liquid is heatedEvaporation occurs when a liquid is heated
at a high temperature and turns into a gas.at a high temperature and turns into a gas.
When a pot of water is on the stove andWhen a pot of water is on the stove and
heated the molecules in the water begin toheated the molecules in the water begin to
move around rapidly and become ‘excited’.move around rapidly and become ‘excited’.
They move so quickly theyThey move so quickly they
separate from each otherseparate from each other
and from the liquid as steam.and from the liquid as steam.
14. CondensationCondensation
When cold temperatures are applied to gas,When cold temperatures are applied to gas,
the molecules in the gas will turn into athe molecules in the gas will turn into a
liquid.liquid.
On a cold morning water vapor (gas) can beOn a cold morning water vapor (gas) can be
seen collecting on the window like mist,seen collecting on the window like mist,
when so much of this water vapour gatherswhen so much of this water vapour gathers
on the cold window the molecules cool andon the cold window the molecules cool and
slow down and join (condense) backslow down and join (condense) back
together to create droplets of water.together to create droplets of water.
