Summary Students model the molecules in three states of matter. Science content Chemistry: States of Matter, Properties of Materials (K-7) Chemistry: Atoms, Molecules (3-7) Science competencies (+ questioning + manipulation + others that are in every activity) Processing/analyzing: classifying data, finding patterns (1 up) Evaluating: inferring (3 up) Lessons activity is in Foods Chemistry States of Matter and State Changes Physical changes in Buttered popcorn The Particles of Matter Water cycle Materials Space for the students to move around in (classroom or outdoors) Procedure Optional: start by reviewing the states of matter, while asking students to find examples in the classroom. Solids have a fixed shape and are hard. Liquids can change shape, but always take up the same amount of space (same volume) as they flow in their container. Gases change shape and fills the space they are in (so change volume). Some students might mention plasma, the 4th state of matter. The particles (molecules or atoms) are arranged differently in different states of matter. Tell students that they will model the particles in each of the three states of matter. They are each a molecule. Ask them to stand in an open space of the classroom. In a solid the molecules are packed tight, held together by strong bonds. Ask students to model a solid by linking arms with their neighbours, so that they are packed tight together in a group. The individuals can jiggle a little, but the group maintains its shape. As a solid gains energy the molecules gain energy and can move around more. They are still bonded to each other, but more loosely. Ask students to model a liquid by spreading apart and moving around more, but always touching at least one other student with an outstretched arm. The bonds between molecules break and form continuously, so that the group stays together but can move and change shape, like a liquid. As a liquid gains even more energy the molecules gain enough energy to move completely apart and evaporate. Ask students to break all bonds with each other and move around the room, spreading out to fill the room. Students can be asked to lose energy and become a liquid again (condensation), then a solid (freezing). For younger students, simplify the language: Stand up close together, arms linked. Stay still. You are not moving. You are stuck together, so you cannot change shape. I can see what shape you are. Which state are you? Solid. You have a bit more energy. Now you can move around a little more. Walk around, but always stay touching at least one other person. So you can change shape but stay the same size. Which state are you? Liquid. Now you have even more energy. You can now move around even more, let go of each other. You now can change shape and size. Which state are you? Gas. Videos of educators/students acting out states of matter:https://www.youtube.com/watch?v=FUa3F2CfbPEhttps://www.youtube.com/watch?v=rmBRpuXI5AA Image of particles in the three states: https://www.priyamstudycentre.com/wp-content/uploads/2023/09/change-of-… Longer cartoon video of the particles in solids, liquids, gases at https://www.youtube.com/watch?v=guoU_cuR8EE Notes Students get goofy when they come together as molecules to form a solid, so maybe split into smaller groups to do this (max 3 groups). If each group does it one at a time the other students can also see how a solid keeps its shape and how a liquid flows. Grades taught Gr K Gr 1 Gr 2 Gr 3 Gr 4 Gr 5 Gr 6
