Students observe and measure the characteristics of physical changes such as boiling point, melting point, or solubility, and simple chemical changes such as rusting, burning, or respiration. They identify factors that affect these changes and characteristics that are specific to each.
Students dissolve a sugar cube and the same mass of sugar crystals in equal amounts of water.
They measure the length of time required to dissolve each, and compare these times at different water temperatures. Students use wet steel wool to illustrate that rusting is a non-reversible chemical change. Students use antacid tablets to observe chemical change. They demonstrate their scientific skills and processes when they collect and record data in various formats, or complete tasks such as designing experiments that demonstrate the concepts they have learned. Skills and processes Students design and perform experiments demonstrating physical and chemical changes.