What is Gay-Lussac's law?

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Gay-Lussac’s mathematical expression would be:

P/T

P1 / _T1 = _P2 / _T2_{_}

Example 1. A gas in a container is under a pressure of 3.00 atm at a temperature of 25 ºC. What would the pressure be in the container at 845°C?

Data:

P ₁ = 3.00 atm

T ₁ = 25ºC = 298 K

T ₂ = 845ºC = 1118 K

Q2 ₌ ?

Considering the equation:

P1 / _T1 = _P2 / _T2_{_}

The values are replaced:

3.00 atm / 298 K = P ₂ / 1118 K

Rearranging the equation and clearing the second pressure:

P ₂ = (3.00 atm 1118 K) / 298 K = 11.3 atm

As you can see, the pressure increases along with the temperature.

Daily Applications of the Gay Lussac Law

Tire Pressure – Car tire pressure drops on a cold day and rises on a hot day.
Pressure Cooker – Applying heat to a pressure cooker increases the pressure inside the device. The increase in pressure raises the boiling point of the water, shortening cooking times. Since the container is sealed, the flavors are not lost in the air with the steam.
Aerosol Can – Aerosol cans should not be stored in hot conditions or disposed of by burning, as heating the can increases the pressure of its contents, which may cause it to burst.