Created By : Rina Nayak

Reviewed By : Rajashekhar Valipishetty

Last Updated : May 09, 2023


Our free Grahams law of diffusion Calculator produces the effusion rate of the gas based on the molar mass of both gases, and the effusion rate of one gas. It takes the rate of effusion (or diffusion) of the first gas, the molar mass of the first gas, and the molar mass of the second gas to produce the effusion rate of the second gas easily and quickly.

What is Graham's Law of Diffusion?

Graham's Law states that the rate of effusion or diffusion of a gas is inversely proportional to the square root of the molar mass. The rate of diffusion is the measure of the rate at which two gases mix, and the rate of effusion is the measure at which the gas escapes into the vacuum. The rate of diffusion unit depends on the property chosen.

Graham's Law of Diffusion Formula

The rate of diffusion of a gas is inversely proportional to the square root of its molar mass at a given pressure and temperature.

Graham's Law of Diffusion Formula is along the lines:

R₁/R₂ = √(M₂/M₁)

Where,

R₁ is the effusion rate of gas 1

R₂ is the effusion rate of gas 2

M₂ is the molar mass of gas 2

M₁ is the molar mass of gas 1


Steps to Calculate Graham's Law of Diffusion Rate

  • Get the molar mass of two gases.
    Make a note of the diffusion rate of one gas.
  • Place the observed values in Graham's Law of diffusion formula.
  • Solve the equation to get the unknown diffusion rate of the second gas.

Example:

Find the relative diffusion rate of water (molar mass=18.0152) as compared to hard water (molar mass=20.0276).

Solution:

Given that,

Molar Mass of water (M₁) = 18.0152

Molar mass of hard water (M₂) = 20.0276

Let us assume the rate of diffusion formula of heavy water as one since it has a slower diffusion rate.

r2 = 1

As per the Graham's law

R₁/R₂ = √(M₂/M₁)

R₁/1 = √(20.0276/18.0152)

R₁² = 1.111705

R₁ = 1.05

So, the relative diffusion rate is 1.05

FAQ's on Graham's law of diffusion Calculator

1. What is Graham's Law of Diffusion?

The principal at the provided temperature and pressure, the rate of diffusion of the gas is inversely proportional to the square root of its molar mass.


2. How is Graham's Law of diffusion calculated?

To find Graham's Law of diffusion, you need to make a note of the molar mass of both gases, and the effusion rate of one gas. Substitute the values in the formula to obtain the result.


3. What is the formula for graham's law of diffusion?

Graham's Law of Diffusion rate formula is Rate 1 / Rate 2 = √(Mass 2 / Mass 1).


4. What are the applications of Graham's law?

Graham's law helps in the separation of gases having different densities. It helps in the separation of isotopes of certain elements. It also helps in determining the molecular weight of the unknown gas using diffusion or effusion rates.