Molar Mass of Gas Calculator

How to Use This Calculator

Enter the values for mass (in grams), volume (in liters), temperature (in Kelvin), and pressure (in atm) of the gas. Then click the Calculate Molar Mass button to find the molar mass of the gas.

What This Calculator is Used For

This calculator is used to determine the molar mass of a gas using the ideal gas law. It’s useful in chemistry and physics for identifying unknown gases or confirming the purity of a sample.

Formula Used

Molar Mass (M) = (mass × R × T) / (P × V)
Where:

• mass = mass of the gas (g)
• R = ideal gas constant = 0.0821 L·atm/mol·K
• T = temperature in Kelvin
• P = pressure in atm
• V = volume in liters

Example

Suppose you have 4 grams of a gas in a 2-liter container at 300 K and 1 atm pressure:
M = (4 × 0.0821 × 300) / (1 × 2) = 49.26 g/mol