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Collect some saw dust and a piece of wood. The tiny particles of saw dust are
particles of wood.
All the examples discussed above show that molecules that make up a
substances are the same whether the substance is big or small.
Arrangement
Arrangement
Arrangement of Molecules in Solid, Liquid and Gasof Molecules in Solid, Liquid and Gasof Molecules in Solid, Liquid and Gas
We have learnt that there are three forms of matter, i.e. solid, liquid and gas.
How are molecules in solid, liquid and gas arranged?
Molecules in a Solid
Molecules in solids :
w have no inter-molecular spaces (the space between molecules), so they
cannot move.
w are held together by a strong pull.
w have a fixed shape and volume.
w are arranged in a pattern.
w are very close to each other.
Molecules in a Liquid
Molecules in liquid :
w have a fixed volume but no fixed shape.
w have small inter-molecular spaces which make the structure mobile.
w are not very close to each other.
w are not arranged in any particular pattern.
w are held together by a weaker pull.
Molecules in a Gas
Molecules in gases :
w move at a great speed in all directions.
w exert a weak pull on each other.
w are far apart with large inter-molecular spaces.
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