The Teacher increases the temperature by clicking on the temperature setting [the
representation shows the water begin to boil and the ‘particles’ begin to leave the
liquid]
My particles are quite busy; they’re moving quite a lot and they’ve got
quite a bit of space.
Teacher selects the Gas to Liquid screen with the ‘View Particles’ viewing option
So, we’ve got to presume that’s happening there.
Points at the boiling water in the sauce pan
By moving between these two sequences within the CD-ROM the teacher offers the
students a multimodally realised theoretical filter with which to view the boiling
water shown in the transformation of a gas to a liquid. He offers the students a tool to
imagine with. He also generalises the ‘particles’ beyond a specific transformation -
that is by moving from one sequence to another he visually makes the point that the
‘particles’ are ‘the same’ regardless of the state of matter, rather it is their
arrangement and movement that changes. He introduces the potential to move
between the screens as a resource for thinking, and to generate and check
explanations. The facilities of the CD-ROM enable the teacher to highlight the role of
observation to create and to reveal patterns of behaviour within (school) science.
Finally, by making the ‘particles’ in the boiling water ‘temporarily’ present in this
way the teacher is able to ‘correct’ the disconnection between the water and the steam
expressed by the student in her earlier explanation of condensation.
Explanation of Phenomena
The teacher, having established a fuller view of both of the transformations of ‘states
of matter’ that are represented on the screen, asks the students to describe and to
explain what she can see.
Display on screen is the Gas to Liquid screen with the ‘View Particles’ viewing
option
T: Talk to us Margaret. What’s happening here? What can you notice?
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