How to use the gas kinetic speed calculator
Find RMS speed of gas molecules. Enter molar mass, temperature in the fields above; the rms speed, mean speed, most probable speed are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- M — Molar mass (g/mol)
- T — Temperature (K)
Worked example
With molar mass = 32 g/mol, temperature = 300 K, the calculator gives rms speed ≈ 483.5745 m/s; mean speed ≈ 445.5257 m/s; most probable speed ≈ 394.8369 m/s.
Frequently asked questions
What is the formula for the gas kinetic speed calculation?
RMS speed (m/s) = √(3 × RGAS × T / (M / 1000)). Mean speed (m/s) = √(8 × RGAS × T / (π × M / 1000)). Most probable speed (m/s) = √(2 × RGAS × T / (M / 1000)). Here M is molar mass (g/mol), T is temperature (K).
What inputs do I need for the gas kinetic speed calculator?
You need molar mass in g/mol, temperature in K. 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 this 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 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.