X

Gay-Lussac's law is an ideal gas law where at constant volume; the pressure of an ideal gas is directly proportional to its absolute temperature. In other words, the law states the principle that, for relatively low pressures, the density of an ideal gas at constant pressure varies inversely with the absolute temperature of the gas.

Gay-Lussac's Law

Table of Contents:

**Formula**

P_{i}/T_{i} = P_{f}/T_{f}

Or

P_{i}T_{f} = P_{f}T_{i}

**Where,**

P_{i} = initial pressure

T_{i} = initial temperature

P_{f} = final pressure

T_{f}= final temperature

n other words, when temperature increases, pressure increases.

When pressure decreases, temperature decreases.

__Example__:

Calculate and find the temperature of the gas which has a pressure of 25 kPa.

Initial Pressure (Pi) = 25 kPa

Initial Temperature (Ti) = 5 K

Final Pressure (Pf) = 15 kPa

__Solution__:

**Apply Formula:**

P_{i}/T_{i} = P_{f}/T_{f}

**Final Temperature (Tf) = 3K**