Look at butter before and after heating. What changed?
- The butter melted and spread out like a liquid. (correct answer)
- The butter froze and became a hard ice cube.
- The butter turned bright blue after heating.
- The butter stayed a cold, hard stick shape.
Explanation: This question tests the skill of observing materials before and after heating or cooling and describing observable changes (2-PS1-4). When we heat materials, they can change—some melt (solid to liquid), some get soft, some change color. Before heating, the butter was a cold, hard stick with a definite shape. After heating, the butter melted and spread out like a liquid—it changed from solid to liquid. The correct answer is A because it accurately describes the observable change—butter melted and spread out like a liquid. D is incorrect because it claims no change when heating actually causes butter to melt. To help students observe heating/cooling changes: Emphasize observation: What do you SEE change? (state from solid to liquid) What do you FEEL change? (temperature gets warmer, texture gets softer). This change is reversible—melted butter can solidify again when cooled.