1. It is a heating curve. I know because the temperature generally increases over time as heat is added.
2. A-B: Solid, B-C: Solid/Liquid (melting), C-D: Liquid, D-E: Liquid/Gas (boiling), E-F: Gas.
3. Yes, the substance is H₂O. I know because its melting point is 0°C and its boiling point is 100°C at standard pressure, which are the known phase change temperatures for water.
4. 0°C
5. 100°C
6. At 2 minutes (point B).
7. Point F. I know because kinetic energy is directly related to temperature, and point F has the highest temperature on the graph.
8. 9 minutes (from 2 minutes to 11 minutes).
9. A-B, C-D, and E-F. During these segments, the temperature (and thus kinetic energy) is increasing while the substance is in a single phase, so potential energy remains constant.
10. B-C and D-E. During these plateaus, the temperature (kinetic energy) is constant while heat is being absorbed to break intermolecular forces, increasing potential energy.
Parent Tip: Review the logic above to help your child master the concept of heating cooling curve worksheet.
