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TGSU3: Addressing the issues (1) LINKS Properties of the particles Teaching approaches that focus on the strengths of forces between particles in each state reinforce the notion of three different types of stuff (solids with strong forces, liquids, etc.) and hence three different types of particle (Model B). The basic particle model used in Stuff & Substance is innovative in that it distinguishes substances and includes the forces between particles - described as ‘ability to hold’ - in images and animations. The latter is pivotal in developing an understanding of the properties of states as collective properties of the particles: differences in the ability of particles to hold on to each other explain different melting and boiling points and hence different room temperature states. (for example, iron particles have a strong ability to hold on to each other, while oxygen particles have a very weak ability to hold on to each other). Crucially, this holding ability does not change in a change of state. This makes models relying on the physical qualities of the particles (Model B above) redundant. not applicable more info tgsu1: notes tgsu2: notes tgsu3: notes tgsu4: notes tgsu5: notes tgsu6: notes more info   < prev | next >

a Science Enhancement Programme CD-ROM 2005   user guide