Why
different melting points? Notes on the animations
Students should notice that
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Both animations show a pattern
using just one kind of shape, to represent one kind
of particle. |
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Both show particles which are
shaking or vibrating, but not moving to a new position. |
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The lead particles are shown
by a different shape from the wax particles. |
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The lines on the
lead particle animation are thicker: this is to show
that the lead particles have a stronger hold on each
other. |
Notes on ‘Think for Yourself’ question.
‘Why does lead have a higher melting point than
wax?’
Suggestions for what might be in a good answer are shown below:
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The lead particles’ holding
power is greater than the holding power of the wax particles.
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This means that the
lead particles need more energy before they have enough
to break out of position and move around. |
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Heating the lead up to a higher
temperature supplies this energy. |
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