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Concept module

Specific Heat and Phase Change

See why the same energy pulse changes different materials by different temperature amounts, and why a phase-change shelf can absorb or release energy without changing temperature on one compact thermal bench.

The simulation shows one bounded thermal bench with a sample container, a heater-or-cooler energy stream, a thermometer, a shelf bar, and a thermal-state card. The same mass, specific heat, power, starting temperature, latent heat, and hidden phase fraction drive every visible part of the bench. Changing the controls updates the same live state for the stage, the readout card, the heating curve, the energy-bookkeeping graph, the response graphs, compare mode, prediction mode, and challenge checks. At t = 0 min, a 1.4 kg sample with specific heat 2.1 kJ/(kg degC) is at -15 degC. The total added energy is 0 kJ, split into 0 kJ of temperature-changing energy and 0 kJ on the phase shelf. Away from the shelf, the current temperature is rising at 6.12 degC/min.

Interactive lab

Keep the stage, graph, and immediate control feedback in one working view.

Time

0.00 s / 18.0 sLivePause to inspect a specific moment, then step or scrub through it.
0.00 s18.0 s

Specific Heat and Phase Change

One compact thermal bench keeps specific heat, phase-change energy, the heating curve, and the current stage readout tied to the same honest energy bookkeeping.

Thermal benchsolid-likeheatersamplesame energy input can change T or phase fractionphase T = 0 degCm = 1.4 kgc = 2.1P = 18 kJ/minT = -15 degCm c = 2.94 kJ/degCdT/dt = 6.12 degC/minLarger m c means the same power changes temperature less each minute.Phase-change shelffraction = 0%mL = 364 kJEnergy change splitsensible = 0 kJlatent = 0 kJHeating curves are honest only when the same energy bookkeeping drives temperature, phase fraction, graphs, compare mode, and challenge checks together.Live: T = -15 degC, latent share = 0%, Q = 0 kJThermal statem1.4 kgc2.1 kJ/kg CP18 kJ/minT-15 degCdT0 degCm c2.94 kJ/Cphase0%Away from the shelf, larger m c means the same power warms the sample more slowly.Shelf width = 364 kJ, so a 18 kJ/min source would need about 20.22 min to cross it.

Graphs

Switch graph views without breaking the live stage and time link.

Heating curve

Track the live temperature against the fixed phase-change temperature. Sloped stretches show sensible heating or cooling, and the flat shelf shows latent-energy change.

time (min): 0 to 18temperature (degC): -20 to 10
TemperaturePhase-change temperature
Heating curveTrack the live temperature against the fixed phase-change temperature. Sloped stretches show sensible heating or cooling, and the flat shelf shows latent-energy change.04.5913.518-20-12.5-52.510time (min)temperature (degC)
Hover or scrub to link the graph back to the stage.time (min) / temperature (degC)

Controls

Adjust the physical parameters and watch the motion respond.

1.4 kg

Changes how much sample is present while keeping the same bounded one-material bench.

2.1 kJ/(kg degC)

Raises or lowers how much energy each kilogram needs for each degree of temperature change.

18 kJ/min

Positive values heat the sample and negative values cool it.

-15 degC

Moves the starting point to a lower slope, the shelf, or an upper slope.

More tools

Secondary controls, alternate presets, and less-used toggles stay nearby without crowding the main bench.

Hide
260 kJ/kg

Changes how much energy the shelf absorbs or releases before temperature changes again.

More presets

Presets

Predict -> manipulate -> observe

Keep the active prompt next to the controls so each change has an immediate visible consequence.

MisconceptionPrompt 1 of 1
A flat heating-curve shelf does not mean the heater stopped. Check the energy-bookkeeping graph and the shelf bar: the latent term can still be changing while temperature stays near the phase-change temperature.

Try this

Use On the shelf, scrub through the flat region, and compare the temperature line with the latent-energy line.

Equation map

See each variable before you move it.

Select a symbol to highlight the matching control and the graph or overlay it most directly changes.

Mass
1.4 kg

Mass scales both the temperature-changing capacity m c and the shelf width m L, so larger samples warm more slowly and need more energy to finish the phase change.

Graph: Heating curveGraph: Shelf width vs latent heatGraph: Temperature change vs specific heatOverlay: Thermal-capacity cueOverlay: Shelf cueOverlay: Energy split

Equations in play

Choose an equation to sync the active symbol, control highlight, and related graph mapping.

More tools

Detailed noticing prompts, guided overlays, and challenge tasks stay available without taking over the main bench.

Hide

What to notice

Use one prompt at a time. Each one keeps specific heat, phase change, and heating-curve reading tied to one compact state.

MisconceptionPrompt 1 of 1
Graph: Heating curve
A flat heating-curve shelf does not mean the heater stopped. Check the energy-bookkeeping graph and the shelf bar: the latent term can still be changing while temperature stays near the phase-change temperature.

Try this

Use On the shelf, scrub through the flat region, and compare the temperature line with the latent-energy line.

Why it matters

This is the beginner-safe way to read a heating curve honestly.
Control: Heating or cooling powerControl: Latent heat LGraph: Heating curveGraph: Energy bookkeepingOverlay: Shelf cueOverlay: Energy splitEquationEquation

Guided overlays

Focus one overlay at a time to see what it represents and what to notice in the live motion.

4 visible

Overlay focus

Thermal-capacity cue

Shows the live m c value and the current temperature rate so the specific-heat idea stays attached to the same sample.

What to notice

  • When m c is larger, the same power makes the sloped parts of the heating curve less steep.

Why it matters

It keeps specific heat tied to a rate of temperature change instead of to a disconnected material label.

Control: MassControl: Specific heat cControl: Heating or cooling powerGraph: Heating curveGraph: Temperature change vs specific heatEquationEquationEquation

Challenge mode

Use the same thermal bench for specific-heat and shelf targets. The checks read the live temperature change, phase fraction, and graph state from one honest simulation state.

0/2 solved
MatchStretch

1 of 9 checks

Same pulse, smaller delta T

Start from Low-c warm sample, switch to compare mode, and edit only Setup B until both setups use the same 4 minute pulse but Setup B warms much less because its specific heat is larger.
Compare modeInspect timeGraph-linkedGuided start

Suggested start

Pause both setups at 4 minutes and edit only Setup B.
Pending
Stay in compare mode while editing Setup B.
Explore
Pending
Open the specific-heat response graph.
Heating curve
Matched
Keep the thermal-capacity cue visible.
On
Pending
Pause into inspect mode.
live
Pending
Check the setups at about four minutes.
0 min
Pending
Keep Setup A near the low-c baseline.
Pending
Setup A should warm a lot under the pulse.
Pending
Raise Setup B to a much larger specific heat.
Pending
Setup B should warm much less under the same pulse.

The checklist updates from the live simulation state, active graph, overlays, inspect time, and compare setup.

At t = 0 min, a 1.4 kg sample with specific heat 2.1 kJ/(kg degC) is at -15 degC. The total added energy is 0 kJ, split into 0 kJ of temperature-changing energy and 0 kJ on the phase shelf. Away from the shelf, the current temperature is rising at 6.12 degC/min.
Equation detailsDeeper interpretation, notes, and worked variable context.

Thermal capacity

Mass and specific heat together set how much energy is needed for each degree of temperature change.

Mass 1.4 kg Specific heat 2.1 kJ/(kg degC)

Temperature-changing energy

Away from the shelf, the energy that changes temperature is proportional to mass, specific heat, and temperature change.

Mass 1.4 kg Specific heat 2.1 kJ/(kg degC) Starting temperature -15 degC

Energy transferred at a fixed rate

A heater or cooler transfers energy at a rate, so the total transferred energy grows with time.

Heating or cooling power 18 kJ/min

Phase-change energy

Crossing the full shelf requires latent energy that depends on both mass and the latent heat of the material.

Mass 1.4 kg Latent heat 260 kJ/kg

Heating-curve bookkeeping

A heating or cooling curve is honest only when the total transferred energy is split between temperature change and phase change.

On a sloped segment, most of the transferred energy is sensible.
On the shelf, the latent term can keep changing while temperature stays nearly fixed.
Mass 1.4 kg Specific heat 2.1 kJ/(kg degC) Heating or cooling power 18 kJ/min Starting temperature -15 degC Latent heat 260 kJ/kg

Progress

Not startedMastery: NewLocal-first

Start exploring and Open Model Lab will keep this concept's progress on this browser first. Challenge mode has 2 compact tasks ready. No finished quick test, solved challenge, or completion mark is saved yet.

Let the live model runChange one real controlOpen What to notice

Try this setup

Copy the live bench state and reopen this concept with the same controls, graph, overlays, and compare context.

Stable links

Starter track

Step 4 of 40 / 4 complete

Thermodynamics and Kinetic Theory

Earlier steps still set up Specific Heat and Phase Change.

1. Temperature and Internal Energy2. Ideal Gas Law and Kinetic Theory3. Heat Transfer4. Specific Heat and Phase Change

Previous step: Heat Transfer.

Start from track beginning

Short explanation

What the system is doing

Specific heat tells you how much energy a material needs for each kilogram to change temperature by one degree. On this compact thermal bench, the same power input can produce a large temperature change in a low-c sample and a much smaller temperature change in a high-c sample because the energy is being spread across a different thermal capacity.

Phase change adds a second idea. A sample can keep absorbing or releasing energy while its temperature stays nearly flat if that energy is changing the phase fraction instead of changing the average thermal motion. That is why a heating curve can contain a real shelf without the heater turning off.

This page stays bounded on purpose. It uses one specific heat, one phase-change temperature, and one latent-heat shelf so the learner can read Q = m c delta T, Q = P t, and Q = m L on one honest state before moving to more detailed chemistry or materials models.

Key ideas

01The thermal capacity of a sample is m c, so the same energy input changes temperature less when the sample is more massive or has a larger specific heat.
02Away from a phase-change shelf, the temperature-changing part of the energy obeys Q_sensible = m c delta T.
03On the shelf, energy can still enter or leave the sample while temperature stays almost flat because the energy is changing the phase fraction instead.
04A heating curve is honest only when the same energy bookkeeping explains both the sloped stretches and the flat shelf.

Live worked example

Solve the exact state on screen.

Use the current bench directly. The same sample, heating curve, and energy bars drive both worked examples, so specific heat and phase change stay tied to one state.
Live valuesLive at t = 0.00 s

At the current inspected time , how much energy has been added, and how much of that energy is actually changing temperature for the current sample?

Sample mass

1.4 kg

Specific heat

2.1 kJ/(kg degC)

Heating or cooling power

18 kJ/min

Thermal capacity

2.94 kJ/degC

1. Compute the total energy transfer

Use , so the total energy transfer is 0\,\mathrm{kJ}$.

2. Build the sample's thermal capacity

For this sample, .

3. Separate the temperature-changing part from the shelf part

Right now 0\,\mathrm{kJ} is changing the phase state, so the live temperature change is 0\,\mathrm{degC}$.

Current energy split and temperature response

The temperature response is being set by m c: the sensible part of the energy divided by the thermal capacity gives the live delta T.

Common misconception

If temperature is not changing, no energy can be entering or leaving the sample.

A flat temperature line can still correspond to real energy transfer when the sample is on a phase-change shelf.

In that case the energy is changing the phase fraction, so the latent-energy term changes while the temperature stays near the phase-change temperature.

Mini challenge

Two 1.4 kg samples receive the same 48 kJ pulse. Sample A has a much larger specific heat than Sample B, and neither sample reaches the phase shelf during the pulse. Which sample changes temperature more, and why?

Prediction prompt

Decide whether the same total energy input guarantees the same temperature change.

Check your reasoning

Sample B changes temperature more because its thermal capacity m c is smaller.
The same total input Q does not force the same delta T. Away from the shelf, the temperature response is Q_sensible divided by m c, so the sample with the smaller m c changes temperature more.

Quick test

Variable effect

Question 1 of 5

Answer from the energy bookkeeping, not from a slogan. The goal is to connect specific heat, latent heat, and heating-curve reading on one bench.

Two equal-mass samples get the same energy pulse and stay away from the shelf. One has a much larger specific heat. Which statement is best?

Choose one answer to reveal feedback, then test the idea in the live system if a guided example is available.

Accessible description

The simulation shows one bounded thermal bench with a sample container, a heater-or-cooler energy stream, a thermometer, a shelf bar, and a thermal-state card. The same mass, specific heat, power, starting temperature, latent heat, and hidden phase fraction drive every visible part of the bench.

Changing the controls updates the same live state for the stage, the readout card, the heating curve, the energy-bookkeeping graph, the response graphs, compare mode, prediction mode, and challenge checks.

Graph summary

The heating-curve graph compares the live temperature with the fixed phase-change temperature so the sloped stretches and the shelf stay aligned with the stage. The energy-bookkeeping graph compares the total transferred energy with the sensible and latent parts on the same time axis.

The specific-heat response graph sweeps only c to show how the same pulse changes temperature less when thermal capacity is larger. The latent response graph sweeps only L to show how a larger latent heat widens the shelf in energy.