Primary 4 – Science: Changing State
“Can a solid change into a liquid and a liquid back into a solid? What happens to the particles during these changes?” These intriguing questions guided P4 students in their exploration of changing states of matter through a melting candle experiment.
Building on their prior knowledge that all matter is made up of particles, students began by recalling how particles are arranged and move differently in solids, liquids, and gases. With this foundation, they conducted an experiment to observe the transition of solid wax to liquid and back to solid.
During the experiment, students noticed that solid wax melted when heated by the candle flame, becoming liquid. As the liquid wax cooled, it solidified once again. Through observation and discussion, students discovered that when a solid is heated, its particles gain heat energy, break free from their fixed positions, and move around, causing the solid to become a liquid. Conversely, when a liquid cools, its particles lose heat energy, settle into fixed positions, and return to a solid state.
This hands-on activity allowed students to observe and explain the process of melting and solidifying, connecting their findings to the particle model of matter. The experiment provided a meaningful and engaging way for students to deepen their understanding of how states of matter change and how particles behave during these transitions, bridging their theoretical knowledge with real-world applications. ***
