Graham's Law Calculator Formula
Understand the math behind the graham's law calculator. Each variable explained with a worked example.
Formulas Used
Rate₁ / Rate₂
rate_ratio = sqrt(molar_mass_2 / molar_mass_1)Variables
| Variable | Description | Default |
|---|---|---|
molar_mass_1 | Molar Mass of Gas 1(g/mol) | 2 |
molar_mass_2 | Molar Mass of Gas 2(g/mol) | 32 |
How It Works
Graham's Law of Effusion
Formula
Rate₁ / Rate₂ = √(M₂ / M₁)
Where:
Lighter gases effuse faster. The rate is inversely proportional to the square root of molar mass.
Worked Example
Compare effusion rates of H₂ (2 g/mol) and O₂ (32 g/mol).
- 01Rate₁/Rate₂ = √(M₂/M₁)
- 02Rate₁/Rate₂ = √(32/2)
- 03Rate₁/Rate₂ = √16
- 04Rate₁/Rate₂ = 4.0
- 05H₂ effuses 4 times faster than O₂
Frequently Asked Questions
What is Graham's Law?
Graham's Law states that the rate of effusion of a gas is inversely proportional to the square root of its molar mass. Lighter molecules move faster.
What is the difference between diffusion and effusion?
Effusion is gas escaping through a tiny hole into a vacuum. Diffusion is mixing of gases through space. Graham's Law applies exactly to effusion and approximately to diffusion.
How was uranium enriched using this law?
In the Manhattan Project, UF₆ gas was effused through barriers. ²³⁵UF₆ (lighter) effused slightly faster than ²³⁸UF₆, gradually separating the isotopes.
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