Calculator Input
Use the default water properties or enter custom values.
Example Data Table
| Substance | Mass | Initial | Target | Melting Point | Boiling Point | Total Heat |
|---|---|---|---|---|---|---|
| Water | 0.5 kg | -20 °C | 120 °C | 0 °C | 100 °C | 1545.5 kJ |
| Ice to water | 1.0 kg | -10 °C | 25 °C | 0 °C | 100 °C | 459.4 kJ |
| Steam heating | 0.2 kg | 100 °C | 180 °C | 0 °C | 100 °C | 32.16 kJ |
Formula Used
The calculator combines sensible heat and latent heat segments.
- Sensible heating: q = m × c × ΔT
- Melting plateau: q = m × Lf
- Boiling plateau: q = m × Lv
Here, m is mass, c is specific heat capacity, ΔT is temperature change, Lf is latent heat of fusion, and Lv is latent heat of vaporization.
Total heat equals the sum of every segment crossed between the initial and target temperatures.
Exact transition temperatures are treated as phase plateaus when the target moves beyond that boundary.
How to Use This Calculator
- Enter the substance name for your reference.
- Choose mass and its unit.
- Enter initial and target temperatures on one scale.
- Provide melting and boiling points.
- Enter specific heats for solid, liquid, and gas phases.
- Enter latent heats of fusion and vaporization.
- Choose J or kJ for the result display.
- Press calculate to view the segment table and graph.
- Use export buttons to save CSV or PDF output.
Frequently Asked Questions
1. What does this calculator compute?
It calculates the total heat needed to move a substance from one temperature to another, including sensible heating within phases and latent heating during melting or boiling plateaus.
2. Can I use substances other than water?
Yes. Enter your own melting point, boiling point, specific heats, and latent heats. The calculator then builds a custom heating path for that material.
3. Why are there flat sections on the graph?
Flat sections represent phase changes. Heat is still added, but temperature stays constant while the substance melts or vaporizes.
4. Which units should I enter for heat capacity?
Enter specific heat values in kJ/kg·°C or kJ/kg·K, and latent heat values in kJ/kg. Temperature differences are numerically identical for Celsius and Kelvin intervals.
5. Does the calculator work when no phase change occurs?
Yes. If the temperature range stays inside one phase, the result reduces to a simple sensible heat calculation using q = m × c × ΔT.
6. Why must target temperature be higher?
This page models a heating curve. A cooling process follows similar ideas, but the sign and sequence of segments would be reversed.
7. What does the cumulative energy column show?
It shows the running total after each stage. This helps you see how much energy is spent on warming versus phase change plateaus.
8. Are the exports suitable for reports?
Yes. CSV is useful for spreadsheets, while PDF is helpful for sharing calculation summaries, result tables, and the plotted heating curve.