Created By : Rina Nayak

Reviewed By : Rajashekhar Valipishetty

Last Updated : Apr 03, 2023

Gay Lussac's Law Calculator gives the unknown parameters such as temperature and pressure of the Gay Lussacs law easily. It just takes the known parameters initial, final pressure and temperature in the input fields and produces the unknown value as result quickly.

Choose a Calculation
Initial Pressure(p1):
Initial Temprature(t1):
Final Pressure(p2):
Final Temprature(t2):

What is Gay Lussac's Law?

Gay Lussac's Law also called the pressure law that states that the pressure exerted by a gas is directly proportional to the absolute temperature of the gas.

It was formulated by the French chemist Joseph Gay-Lussac in the year 1808. This law tells that pressure is proportional to the temperature when there is a constant amount of gas in a closed and rigid container.

Gay Lussac's Law Formula

From the Gay Lussac's Law definition, its formula is P₁/T₁ = P₂/T₂.


  • P₁ is the initial pressure
  • T₁ is the initial temperature
  • P₂ is the final pressure
  • T₂ is the final

The relationship between the pressure and temperature of a gas can be P₁/P₂ = T₁/T₂.

Gay Lussac's Law Derivation

Gay Lussac's Law states that pressure is proportional to the temperature.

P ∝ T

P/T = k

For two different conditions of a gas,

P₁/T₁ = k --- (i)

P₂/T₂ = k --- (ii)

Equating both equations

P₁/T₁ = P₂/T₂

Gay Lussac's Law Example:

Question: The pressure of a gas in a cylinder when it is heated to a temperature of 220K is 1.8 atm. What was the initial temperature of the gas if its initial pressure was 1 atm.


Given that,

Initial pressure P₁ = 1 atm

Final pressure P₂ = 1.8 atm

Final temperature T₂ = 220K

Gay Lussac's Law formula is P₁/T₁ = P₂/T₂

T₁ = (P₁T₂)/P₂

= (1 * 220)/1.8

= 220/1.8

= 122.2

Therefore, the final temperature of the gas is 122.22 K.

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Frequently Asked Question’s on Gay Lussac's Law Gas Calculator

1. What is the Gay Lussac's Law formula?

Gay Lussac's Law formula is P₁/T₁ = P₂/T₂.

2. What are the 5 gas laws?

The five gas laws are Boyle's law, Charle's law, Gay Lussac's Law, Avogadro's law, and ideal gas law.

3. How is Gay Lussac's Law calculated?

This law states that absolute pressure is directly proportional to the temperature. By using Gay Lussac's Law Equation, you can find the unknown parameters easily.

4. What is the importance of Gay Lussac's Law?

Gay Lussac's Law is a law that illustrates that increasing the gas temperature induces a relative increase in its pressure when the volume is constant.

Gay Lussac's Law Calculator