Teach lesson
Heating and Cooling Curves of Water: phase changes from real video
Students use the UFH Water Heating and Cooling Curves remote lab to read real thermometer-video frames, compare high heat, low heat, and cooling, graph temperature against time, and explain phase-change plateaus.
Learning Outcomes
Use a real remote lab to collect temperature-time evidence from video.
Distinguish warming/cooling slopes from phase-change plateaus.
Compare low-heat, high-heat, and ice-cooling runs using controlled observation.
Calculate a temperature-change rate from frame-read evidence.
Explain why temperature can stay nearly constant during a phase change.
Write a bounded claim that names video-reading uncertainty.
Student activity preview
Activity Content
Preview only. In a class session, students can fill in responses and submit their work to the teacher.
Predict the curve before measuring
8 min
The remote lab lets you heat ice/water with low or high heat, or cool hot water in an ice bath. You will not receive a spreadsheet from the lab. You will build evidence by reading the thermometer video at clear timestamps.
The real video evidence
The lab has two synchronized views: a process camera and a thermometer camera. Temperature readings are frame estimates, so record the timestamp and clarity of each reading.
Temperature-change rate
\text{rate of temperature change} = \frac{\Delta T}{\Delta t}
Before opening the lab, predict the shape of a heating curve for water that starts as ice. Include what you expect near melting, what happens once liquid water is warming, and how high heat should differ from low heat.
During a phase-change plateau, energy is still being transferred. What is the best explanation?
Use the video lab deliberately
10 min
The lab route for this activity uses exactly three configurations: low-heat heating, high-heat heating, and ice cooling. Run all three from the TEACH-launched lab and keep every temperature row tied to its run setting.
Observation workflow
Keep each row tied to its run setting. Do not average heating and cooling rows together.
Open the Water Heating and Cooling Curves lab
Open the Water Heating and Cooling Curves lab from TEACH.
The lab starts on the introduction screen. Use the numbered steps to move to
2 - Configuration.Choose
HeatingandLow heat, then move to3 - Observation. Watch both the process camera and thermometer camera.Use 1x for careful thermometer readings; use 5x only to move through parts you are not recording.
For the low-heat run, record two separated rows near the 0 C melting region and at least two later rows from the warming liquid-water part.
Repeat with
HeatingandHigh heat, using early, middle, and hot-water rows.Repeat with
CoolingandIce, using early, middle, and late rows.For every row, record the run setting, timestamp, temperature, and display clarity.
In the evidence-origin column, write
live videofor rows you read yourself orteacher rowfor any row supplied by your teacher.
Which plan matches what this lab lets you do?
Collect frame-read temperature evidence
18 min
Use clear readings first. If a frame is blurred or a digit is ambiguous, write uncertain and either choose a nearby clearer frame or explain the uncertainty. Use two separated near-0 C rows to support your plateau explanation. Do not use those plateau rows for the low-heat slope calculation; use two later rows after the temperature has started rising.
Frame-reading discipline
Every numerical row should have a timestamp, temperature, run setting, and clarity note.
Temperature-time evidence table
Record real video-frame readings. Use seconds or the lab counter consistently. Required route: two separated low-heat rows near the melting plateau plus two later warming rows; cooling early, middle, and late; high heat early, middle, and hot-water rows. For evidence origin, write live video or teacher row. Do not use plateau rows for the low-heat slope calculation.
| Run setting | Evidence origin | Time s | Temperature C | Display clarity | Interpretation note |
|---|---|---|---|---|---|
Name one reading you trust and one reading you treated cautiously. For each, state the run setting, timestamp, temperature, and why the display was clear or uncertain.
Analyze slopes and curve shape
12 min
Now use the table to compare what each curve is doing. Heating and cooling answer different questions, so analyze them separately.
Curve graph scaffold
Use this scaffold to check your axes and labels before you plot your own frame-read rows.
Using two low-heat rows from the rising liquid-water part after the near-0 C melting region, estimate a temperature-change rate. Show the two points and calculate temperature change divided by time change.
Use your cooling rows to decide where cooling was faster or slower during the run. Cite at least two intervals or rows.
Use your rows to compare high heat and low heat. What differs about the slope or time to reach hot-water temperatures? What should not change about water's melting temperature, and what would only be a boiling-temperature claim if a run actually reached boiling?
Optional graph: create and explain your graph
8 min
If your teacher assigns a graph, make a temperature-time graph. Graph all three runs together if the axes are readable, or make one graph comparing low-heat and high-heat heating plus a second graph for cooling.
Heating/cooling curve graph
Optional if assigned: attach a graph file, spreadsheet, screenshot, or link to a graph you made from your temperature rows. It must show temperature in C against time for all three run settings, or one low/high heating graph plus one cooling graph. Label which points came from live lab readings.
Describe the graph you made. State the x-axis, y-axis, units, run settings, and one segment or plateau you labelled.
Explain the phase-change evidence
12 min
Use your rows, and your graph if your teacher assigned one, to write a scientific conclusion. A good conclusion does not pretend the video readings are perfect.
Explain why temperature can stay nearly constant while energy is still being transferred during melting. Use particle-level language such as arrangement, spacing, or attractions between particles. Discuss boiling only if your run actually reached it.
Name two limitations or uncertainty sources in this remote-lab activity. At least one must be about reading temperature from video. For each one, explain how it could affect your conclusion.
Write a claim-evidence-reasoning conclusion of 6-8 sentences. Include:
- your claim about the heating/cooling curve shape;
- two numerical evidence details;
- what high heat changes compared with low heat;
- why plateaus happen;
- one limitation of the evidence.
Optional extension: real-time rates
15 min
If your teacher asks for a quantitative extension, repeat one short section at 1x speed and compare video time with real elapsed time.
How would you design a stronger test of whether high heat has a larger temperature-change rate than low heat? Include:
- how you would convert or control the time scale;
- how you would repeat readings;
- which curve segment you would compare.