Explain that mass is conserved when a substance changes state.

Explain that mass is conserved when a substance changes state. Evidence lens: Use the data, graph feature, practical observation, or particle behaviour that proves the answer. In Changes of state, this means density links mass and volume, so the answer must preserve which quantity is being calculated. The answer should use the approved wording from Changes of state and the particle model, include that, mass, conserved, when, and avoid drifting into another section of Particle model of matter. For revision, practise saying the exact objective aloud, then add the one calculation, particle movement, collision, graph, or practical detail that makes the statement true. A strong exam response for checkpoint 26 is specific to explain that mass is conserved when a substance changes state and does not reuse a generic explanation from a neighbouring objective.