Thermodynamik & Wärmeübertragung · GCSE Physics Topic 3
Phasenübergang & Erwärmungskurven-Simulator
Phasenumwandlungen: Schmelz- und Siedekurven von kristallinen und amorphen Stoffen
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- Echtzeit-Herleitung
- Projektormodus
- A4-Arbeitsblatt
3D-Simulationsfenster● 60 FPS
Experimentelle Steuerungsparameter
W
kPa
g
Echtzeit-Herleitung & Kennzahlen
Schmelzpunkt
--
Siedepunkt
--
Aktuelle Phase
--
Dauer des Schmelzplateaus t = mL/P
--
Echtzeit-Formelherleitung
Grundformel:
--Einsetzungsschritte:
--Physikalischer Zustand: --
Typische Beispielaufgaben & Prüfungsfallen
Worked Problem
Aufgabe: Water temperature plateau holds at 98°C. What is boiling point? Is atmospheric pressure above or below 1 atm?
Schrittweise Herleitung:
- Boiling point is 98°C. Below 1 atm because standard boiling point is 100°C (lower pressure lowers boiling point).
Worked Problem
Aufgabe: Does a 0°C ice cube melt in a perfectly insulated 0°C room? Why?
Schrittweise Herleitung:
- No! Melting requires reaching melting point AND continuing to absorb heat. Zero temperature difference means zero heat transfer.
Arbeitsblatt für den Unterricht & Hausaufgaben
Q1. Variant 1: Why use a water bath rather than direct flame heating in solid melting experiments?
Answer Key: Ensures uniform heating across the entire sample tube and slows the temperature rise rate for accurate observations.
Q2. Variant 2: How do bubble sizes change as they ascend before vs during boiling?
Answer Key: Before boiling: bubbles shrink as water vapor re-condenses in cooler top layers. During boiling: bubbles grow as hydrostatic pressure decreases.
Q3. Variant 3: How does a pressure cooker cook beef rapidly using the pressure-boiling point relationship?
Answer Key: Trapped steam raises internal pressure to ~2 atm, boosting water boiling point to ~120°C, speeding chemical tenderization.
Häufige Fragen & typische Missverständnisse
What physics explains the proverb "It is not cold when snowing, but freezing when snow melts"?
Snow formation is an exothermic release of latent heat. Snow melting absorbs immense latent heat from surrounding air, plunging ambient temperatures.
Why does a 100°C steam scald inflict far more severe tissue burn than 100°C boiling water?
Steam must first condense into boiling water, releasing massive latent heat of vaporization (2260 kJ/kg) before cooling, delivering double heat.
Is the thick white fog billowing around sublimating dry ice gaseous carbon dioxide?
No! CO2 gas is transparent and invisible. The dense fog consists of microscopic liquid water droplets condensed from humid air chilled by dry ice.
Why can a paper pot boil water over an open flame without catching fire?
Paper's ignition point is ~180°C. Boiling water absorbs heat at 100°C plateau, chilling the paper below ignition threshold.