Created By : Rina Nayak

Reviewed By : Phani Ponnapalli

Last Updated : Apr 03, 2023

Free Van der Waals Equation Calculator is here to find the physical parameters of the real gas in a short span of time. Just provide the input details and press the calculate button to know the result immediately.

Choose a Calculation
Pressure(P):
Volume(V):
Amount of Substance(n):
mol
Temprature(T):

### How to Find Gas Parameters?

Have a look at the simple process of calculating the unkown real gas parameters.

• Enter the known details in the input fields of the calculator.
• Click the calculate button.
• You can find the unknown values as result.

### What is meant by Van der Waals Equation?

Van der Waals Equation describes the relationship between the volume, temperature and pressure of the real gas. The two Van der Waals parameters are intermolecular attraction, finite size of the molecule. Thus, the Van der Waals Equation is used to find the physical properties of the gas.

Van der Waals Equation was derived by Johannes Diderik van der Ealls in 1873. It is the modified version of the ideal gas law.

### Ideal Gas Equation and Van der Waals Equation

Van Der Waals Equation is given as (p + a * (n / V)²) * (V / n - b) = R * T

Where,

p is the pressure of the gas

v is the volume of the gas

T is the absolute temperature of the gas

n is the number of moles of gas

R is the gas constant R = 8.3144598 J / (mol * K)

a, b are the van der Waals parameters

Ideal gas law formula is PV = nRT

Example:

Question: Determine the pressure of the gas using the Van der Waals equation where 1 mole of ammonia fills 7-litre bottle at a temperature of 350K. (a= 4.17 atm L²/mol² and b = 0.0371 L/ mol

Given that,

a = 4.17 atm L²/mol²

b = 0.071 L/mol

n = 1

V = 7 liter

T = 350 k

Van Der Waals Equation is (p + a * (n / V)²) * (V / n - b) = R * T

P = (nRT)/(V - nb) - (n²a)/V²

= (1 * 0.0821 * 350)/(7 - 1 * 0.0371) - (1²(4.17)/7²

= 4.04

Therefore, the pressure is 4.04 atm.

If you would like to learn more about the other chemical calculator that gives instant results, stay tuned to Chemistrycalc.Com

### FAQ’s on Van Der Waals Equation Calculator

1. How to use the Van Der Waals Equation Calculator?

You have to enter the known parameters of the gas and hit the calculate button to get the physical properties of the gas.

2. What is the Van Der Waals Equation?

The Van Der Waals Equation is (p + a * (n / V)²) * (V / n - b) = R * T.

3. What is meant by Van Der Waals Equation?

Van Der Waals Equation is the equation that provides the relationship between the pressure, volume and absolute temperature of the real gas. It uses two parameters like intermolecular attraction, the finite size of the molecule. These parameters are called van der Waals parameters.

4. What are the units of Van Der Waals constants?

The unit of "a" is atm lit2/mol2, unit of "b" is litre/mol. 