Energy of Phase Changes
▶︎ Watch it animatedinteractive step-through · ~3 min · optionalA heating curve shows how temperature changes as energy is added. Sloped sections warm a single phase; the flat plateaus are phase changes, where the added energy goes into breaking intermolecular forces rather than raising the temperature. Melting (fusion) and boiling (vaporization) both plateau, but boiling costs more energy than melting.
The misconceptions misread the plateaus (temperature is constant there because energy breaks IMFs, not because nothing is happening) and assume melting and boiling cost the same (vaporization requires more energy than fusion). During a phase change, energy in does not raise the temperature.
The work
3 ways in · any order
Lesson
Phase-Change Energy
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A heating curve's plateaus are phase changes where energy breaks IMFs at constant temperature, and boiling costs more than melting. The lesson reads the curve, then closes with a ten-scenario check.
Diagnostic
10-item topic check
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Ten items spanning the Topic 6.5 misconceptions: heating-curve plateaus misread, melting and boiling assumed equal in cost, and ΔH treated as fixed regardless of amount.
Targeted Practice
Drill a single misconception
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Pick one of the failure modes you missed and drill it on its own. The round is adaptive: two correct in a row clears the misconception and moves you to the next.