Enter the pressure (Pa), the molecular weight (kg/mol), and the temperature (K) into the Density From Molecular Weight Calculator. The calculator will evaluate and display the Density From Molecular Weight.

## Density From Molecular Weight Formula

The following formula is used to calculate the Density From Molecular Weight.

D = P * MW / (R*T)
• Where D is the Density From Molecular Weight (kg/m^3)
• P is the pressure (Pa)
• MW is the molecular weight (kg/mol)
• T is the temperature (K)
• R is the Universal Gas Constant (8.314)

To calculate density from molecular weight, multiply the pressure by the molecular weight, then divide by the product of the temperature and gas constant.

## How to Calculate Density From Molecular Weight?

The following example problems outline how to calculate Density From Molecular Weight.

Example Problem #1

1. First, determine the pressure (Pa).
1. The pressure (Pa) is given as 3000.
2. Next, determine the molecular weight (kg/mol).
1. The molecular weight (kg/mol) is calculated as: .44.
3. Next, determine the temperature (K).
1. The temperature (K) is found to be: 250.
4. Finally, calculate the Density From Molecular Weight using the formula above:

D = P * MW / (R*T)

Inserting the values from above yields:

D = 3000 * .44 / (8.314*250) = .635 (kg/m^3)

Example Problem #2

The variables needed for this problem are provided below:

pressure (Pa) = 240

molecular weight (kg/mol) = 205

temperature (K) = 100

This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer.

D = P * MW / (R*T) = (kg/m^3)