Formula
ΔS=Q_rev/T at constant temperature.
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Constant-temperature reversible heat transfer only. Do not apply Q/T to an arbitrary irreversible or nonisothermal path.
Example Calculation
Example inputs
- Reversible heat into system: 1000 J
- Absolute temperature: 250 K
1000 J reversibly absorbed at 250 K gives ΔS=4 J/K.
Frequently asked questions
How do I use this calculator?
Enter reversible heat into system, absolute temperature. The result updates automatically. Use Reset to restore the example values.
What method does it use?
ΔS=Q_rev/T at constant temperature.. Constant-temperature reversible heat transfer only. Do not apply Q/T to an arbitrary irreversible or nonisothermal path.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.