Heating curve — Science definition
Defined in 2 courses:
- Graph of temperature during energy input. (Physical Science: Matter, Forces & Energy)
- A graph of temperature versus energy added (or time) as a substance is heated; it shows flat plateaus during phase changes. (Physical Science: Chemistry)
Where it is taught
- Heating Curves & Energy During Phase Change — Phases of Matter, Physical Science: Matter, Forces & Energy, Grade 8
- Kinetic Molecular Theory & Phase Changes — States of Matter & Gases, Physical Science: Chemistry, Grade 11
In use
A heating curve is a graph of temperature during energy input.
Heating Curves & Energy During Phase Change
A heating curve separates warming within a phase from changing phase fraction.
Kinetic Molecular Theory & Phase Changes
Questions using heating curve
Problem 1
Answer and explanation
Continued input can change phase fraction and particle interactions while temperature remains nearly steady.
Continued input can change phase fraction and particle interactions while temperature remains nearly steady.
Response criteria
- Use the supplied conditions and relevant evidence.
- Explain the scientific mechanism or calculation.
- State a meaningful limitation or testable next step.
Problem 2
Answer and explanation
No. A phase-change interpretation is supported by the growing liquid fraction, but 12 °C is not ordinary-pressure pure water’s melting point. Composition, pressure and other properties need to be checked.
Use both temperature and phase evidence.
Do not treat every plateau as water melting at a universal temperature.
No. A phase-change interpretation is supported by the growing liquid fraction, but 12 °C is not ordinary-pressure pure water’s melting point. Composition, pressure and other properties need to be checked.
Response criteria
- Use the named labels, directions or supplied quantities accurately.
- Connect the visual evidence to the scientific mechanism or calculation.
- State the relevant model conditions or limitation.
Problem 3
Answer and explanation
No. A phase-change interpretation is supported by the growing liquid fraction, but 12 °C is not ordinary-pressure pure water’s melting point. Composition, pressure and other properties need to be checked.
Use both temperature and phase evidence.
Do not treat every plateau as water melting at a universal temperature.
No. A phase-change interpretation is supported by the growing liquid fraction, but 12 °C is not ordinary-pressure pure water’s melting point. Composition, pressure and other properties need to be checked.
Response criteria
- Use the named labels, directions or supplied quantities accurately.
- Connect the visual evidence to the scientific mechanism or calculation.
- State the relevant model conditions or limitation.
Problem 4
- The substance is cooling down
- The particles have stopped moving completely
- An error was made recording the data
- A phase change is occurring; added energy breaks particle attractions instead of raising the temperature
Answer and explanation
A phase change is occurring; added energy breaks particle attractions instead of raising the temperature
During a phase change the temperature holds steady because the incoming energy goes into breaking attractions (potential energy), not speeding particles up (kinetic energy).
Taught alongside
- phase
- plateau
- latent heat
- coexistence
- model
- evidence
- system boundary
- assumption
- kinetic molecular theory (KMT)
- kinetic energy
- phase change
- heat of fusion
- heat of vaporization
- phase diagram