AboutContact
ConversionMathPhysicsReference
AboutContact

Ideal Gas Law Calculator

0

This calculator allows you to use the Ideal Gas Law to find a missing variable when given the other properties of the gas's environment.

The Ideal Gas Law relates the pressure, volume, temperature, and number of moles of a gas:

PV=nRTPV=nRT

Where:

  • P = Pressure
  • V = Volume
  • n = Amount of substance (in moles)
  • R = Ideal gas constant
  • T = Temperature (in Kelvin)

How to Use This Calculator

  1. Select the variable you want to solve for (P, V, n, or T) using the dropdown menu.
  2. Enter the known values for the other variables.
  3. The calculator will compute the result based on the ideal gas law formula.

The Ideal Gas Constant (R)

In the Ideal Gas Law equation, the constant R used to represent the proportionality between the variables P, V, n, and T.

More specifically, R represents the constant of proportionality between energy, temperature, and the amount of substance something has. This is why it is also known as the gas constant, molar gas constant, and the universal gas constant.

It's derived from the product of the Avogadro constant NA and the Boltzmann constant k.

R=NAkR=N_Ak

Where:

  • NA = 6.02214076 × 1023 mol-1
  • k = 1.380649 × 10-23 J · K-1

Thus, the calculation for R is:

R=6.02214076×1023 mol−1×1.380649×10−23 J⋅K−1R=6.02214076\times 10^{23}\space\text{mol}^{-1}\times 1.380649\times 10^{-23}\space\text{J}\cdot \text{K}^{-1}=8.31446261815324 J⋅K−1 mol−1=8.31446261815324\space\text{J}\cdot \text{K}^{-1}\space\text{mol}^{-1}

Note that this calculator uses 8.314462618 for R, which is still more than enough precision for most applications.

Understanding the Ideal Gas Law

The Ideal Gas Law is a fundamental equation in chemistry and physics that describes the relationship between pressure, volume, temperature, and the number of moles of an ideal gas. It's expressed as:

PV=nRTPV = nRT

This equation combines several simpler gas laws (Boyle's Law, Charles's Law, and Avogadro's Law) into a single, comprehensive expression.

  • Gas particles have negligible volume compared to the space between them.
  • There are no intermolecular forces acting between particles.
  • All collisions between particles (and with container walls) are perfectly elastic, meaning no energy is lost.
  • The gas behaves uniformly at all temperatures and pressures—though this is mainly true at high temperature and low pressure.