Gay-Lussac's Law Tutorial

Gay-Lussac's Law:

Gay-Lussac's Law states that the pressure of a fixed amount of gas at fixed volume is directly proportional to its temperature in kelvins.

Gay-Lussac's Law Example

Case 1: A cylinder contain a gas which has a pressure of 125kPa at a temperature of 200 K. Find the temperature of the gas which has a pressure of 100 kPa.

P_i = 125 kPa, T_i = 200 K, P_f = 100 kPa

Step 1:

Substitute the values in the below final temperature equation: Final Temperature(T_f) = P_fT_i / P_i = (100 x 200) / 100 = 20000 / 125 Final Temperature(T_f) = 160 K This example will guide you to calculate the final temperature manually. Case 2: Find the final pressure of gas at 150 K, if the pressure of gas is 210 kPa at 120 K. P_i = 210 kPa, T_i = 120 K, T_f = 150 K

Step 1:

Substitute the values in the below pressure equation:

Final Pressure(P_f) = P_iT_f / T_i = (210 x 150) / 120 = 31500 / 120 Final Pressure(V_f) = 262.5 kPa This example will guide you to calculate the pressure manually.