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Led by Ludwig Boltzmann Simulacrum
Five tutorials covering AQA GCSE Physics §4.3 Particle Model of Matter — density and states of matter, internal energy and specific heat capacity, latent heat, particle motion in gases, and gas pressure and compression — taught by simulacra of the atomists and kinetic theorists who worked out what matter is made of and how it behaves.
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Led by John Dalton Simulacrum
The question
Why is a block of iron denser than a block of wood, and why is the same water light as steam and heavy as ice?
Territory
ρ = m/V · units (kg/m³) · simple particle diagrams for solids, liquids, gases · why density differs between the three states · mass conservation in changes of state (melting, freezing, boiling, evaporating, condensing, sublimating) · physical versus chemical change (the substance's original properties return if the physical change is reversed) · required practical 5 (determine densities of regular solids, irregular solids, and liquids — using rulers and callipers for regular shapes, displacement technique for irregular shapes)
Outcome
The student can apply the density equation, draw the particle arrangement for each state of matter, explain differences in density in terms of particle arrangement, describe all six changes of state with mass conservation, and carry out Required Practical 5 for regular solids, irregular solids, and liquids. (AQA 4.3.1.1, 4.3.1.2)
Led by Amedeo Avogadro Simulacrum
The question
When you heat a substance, what actually happens to the atoms inside it?
Territory
internal energy defined as total kinetic energy plus potential energy of particles · heating transfers energy to the internal store · two possible outcomes: temperature rise or change of state · ΔE = mcΔθ · specific heat capacity as a property of the substance · molecular interpretation (particles with more ways to store energy have higher heat capacities) · cross-reference to Course 1 Module 3 (Energy)
Outcome
The student can define internal energy, explain what heating does at the particle level, apply ΔE = mcΔθ correctly, and connect the molecular picture to the numerical value of specific heat capacity. (AQA 4.3.2.1, 4.3.2.2)
Led by Joseph Louis Gay-Lussac Simulacrum
The question
Why does boiling water stay at 100 °C no matter how much heat you put in, even though the kettle is still pouring energy into it?
Territory
latent heat as energy for a change of state with no change in temperature · E = mL · specific latent heat defined · latent heat of fusion (solid to liquid) and latent heat of vaporisation (liquid to vapour) · why vaporisation requires more energy than fusion (particles must be fully separated, not merely freed to slide past each other) · interpretation of heating and cooling graphs with plateaus at phase changes · the distinction between specific heat capacity (temperature change) and specific latent heat (phase change) · experiment to measure the latent heat of fusion of water
Outcome
The student can apply E = mL, interpret heating and cooling graphs including plateaus at phase changes, distinguish specific heat capacity from specific latent heat, and perform an experiment to measure the latent heat of fusion of water. (AQA 4.3.2.3)
Led by Ludwig Boltzmann Simulacrum
The question
What IS temperature, at the level of the particles that make up a gas?
Territory
molecules of a gas in constant random motion · temperature of the gas related to the average kinetic energy of its molecules · pressure as arising from collisions of molecules with the walls of the container · qualitative relationship between temperature and pressure at constant volume · what "hot" and "cold" mean at the particle level · the distinction between this qualitative picture and the quantitative gas laws (which follow in Module 5)
Outcome
The student can explain the motion of gas molecules, relate gas temperature to the average kinetic energy of its molecules, and reason qualitatively about the pressure of a gas held at constant volume when the temperature changes. (AQA 4.3.3.1)
Led by Robert Boyle Simulacrum
The question
If you squeeze a sealed syringe, why does the air inside push back — and what happens to the temperature?
Territory
pressure acts at right angles to the surfaces that contain a gas · a gas can be compressed or expanded by pressure changes · pV = constant for a fixed mass of gas at constant temperature · using the particle model to explain why increasing volume decreases pressure · quantitative calculations: given p1, V1, and one of p2 or V2, find the other · (Higher Tier) work done on a gas transfers energy to it, raising internal energy and therefore temperature · worked example: the bicycle pump
Outcome
The student can state Boyle's Law and apply pV = constant to both compression and expansion, use the particle model to explain qualitatively why reducing volume raises pressure, and (Higher Tier) explain how doing work on a gas raises its temperature. (AQA 4.3.3.2, 4.3.3.3)