How to use the entropy of mixing calculator
Find the entropy increase when two ideal gases or liquids mix. Enter moles of component 1, moles of component 2 in the fields above; the entropy of mixing, entropy of mixing per mole are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “entropy of mixing”, “disorder when mixing”, “ideal mixing entropy”, “calculate entropy of mixing”, “find entropy of mixing”.
Formula
Variables
- n1 — Moles of component 1 (mol)
- n2 — Moles of component 2 (mol)
Worked example
With moles of component 1 = 1 mol, moles of component 2 = 1 mol, the calculator gives entropy of mixing ≈ 11.52629 J/K; entropy of mixing per mole ≈ 5.763146 J/(mol·K).
Frequently asked questions
What is the entropy of mixing calculator used for?
Find the entropy increase when two ideal gases or liquids mix. It helps with questions such as “entropy of mixing”, “disorder when mixing”, “ideal mixing entropy”.
What is the formula for the entropy of mixing calculation?
Entropy of mixing (J/K) = -RGAS × (n1 × ln(n1 / (n1+n2))+n2 × ln(n2 / (n1+n2))). Entropy of mixing per mole (J/(mol·K)) = [Entropy of mixing] / (n1+n2). Here n1 is moles of component 1 (mol), n2 is moles of component 2 (mol).
What inputs do I need for the entropy of mixing calculator?
You need moles of component 1 in mol, moles of component 2 in mol. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the entropy of mixing calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the entropy of mixing result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.