Molecules and Matter

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• Molecules and Matter

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Molecules And Matter
All these substances are made from water
molecules but all showing very different
properties because .
One is a SOLID, one is a LIQUID and one is a GAS
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How Molecules Are Arranged In A Solid
Solids Hold their shape
Have a fixed volume

• There are many bonds between molecules in solids.
  
• The molecules are usually held in regular patterns

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Liquids Take up the shape of their
container Have a free side
Have a fixed volume
The molecules are able to move around each other.
They have weak bonds attracting them to other
molecules
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Gasses Expand, contract to the shape of
the
container. Take up the shape of the
container, dont have a fixed volume
The molecules have very little attraction to each
other. There are few bonds between molecules.
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Add HEAT ENERGY to the SOLID and bonds become
weaker producing a LIQUID
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Add HEAT ENERGY to the liquid and the bonds break
down producing a GAS
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• Liquids will flow and take up the shape of their
  container
• When heated solids become a liquid
• These two points are important in technology
  because we can use these properties to form
  intricate shapes using metals. If we heat a metal
  up then pour it into a mould it will take up the
  shape of the mould and keep that shape as it
  cools and becomes solid.
• This is called

CASTING
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How Casting Works
Remove the mould
Pour hot liquid metal into the cavity
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Pewter Casting
A suitable metal to use is pewter and a simple
mould can be made out of an MDF (medium density
fibreboard) sandwich.
How the mould is formed
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The Mould
This is the final MDF mould
Cavity layers. (this mould uses two)
Finished castings
Thicker outer layers
The spout has been cut in the thicker wood with a
round surform
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Safety Safety Safety Safety Safety

• When pouring the HOT pewter
• Wear gloves
• Wear Goggles
• Make sure nobody is near you

• A reciprocating saw can be used to cut the mould.
  This needs
• Goggles
• The guard to be in place
• Training

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These castings are possible because heating a
solid produces a liquid that can be poured. It
will take up the shape of the mould and when it
solidifies it will keep the shape of the mould.
These castings are possible because heating a
solid produces a liquid that can be poured. It
will take up the shape of the mould and when it
solidifies it will keep the shape of the mould.