3. Isobaric and Isochoric Processes of Gases

3. Isobaric and Isochoric Processes of Gases

Concept Explanation:

Isobaric Process: A thermodynamic process that occurs at constant pressure. According to Charles's Law, the volume of a gas is directly proportional to its absolute temperature when the pressure is constant:

V1/T1 = V2/T2

Isochoric Process: A thermodynamic process that occurs at constant volume. According to Gay-Lussac's Law, the pressure of a gas is directly proportional to its absolute temperature when the volume is constant:

P1/T1 = P2/T2

Example Problem (Isobaric):

A gas has a volume of 3 liters at 300 K. If the temperature is increased to 450 K while the pressure remains constant, what will be the new volume?

Solution:

Using Charles's Law:

V1/T1 = V2/T2

Substituting the given values:

3 L / 300 K = V2 / 450 K

V2 = (3 * 450) / 300 = 4.5 L

So, the new volume is 4.5 liters.

Example Problem (Isochoric):

A gas is confined in a rigid container with a pressure of 2 atmospheres at 350 K. What will be the pressure if the temperature is increased to 700 K?

Solution:

Using Gay-Lussac's Law:

P1/T1 = P2/T2

Substituting the given values:

2 atm / 350 K = P2 / 700 K

P2 = (2 * 700) / 350 = 4 atm

So, the new pressure is 4 atmospheres.