Gas Laws

Study Guide: Gas Laws

1. Boyle's Law

  • Definition: At constant temperature, the pressure of a gas is inversely proportional to its volume.

  • Formula: P1V1 = P2V2

  • Key Concept: When the volume increases, pressure decreases, and vice versa.

2. Charles's Law

  • Definition: At constant pressure, the volume of a gas is directly proportional to its temperature in Kelvin.

  • Formula: V1/T1 = V2/T2

  • Key Concept: As temperature increases, volume increases, and vice versa.

3. Avogadro's Law

  • Definition: At constant temperature and pressure, the volume of a gas is directly proportional to the number of moles of gas.

  • Formula: V1/n1 = V2/n2

  • Key Concept: Equal volumes of gases contain equal numbers of molecules at the same temperature and pressure.

4. Ideal Gas Law

  • Definition: Relates pressure, volume, temperature, and number of moles of an ideal gas.

  • Formula: PV = nRT

    • Where P = pressure, V = volume, n = number of moles, R = gas constant, T = temperature.

  • Key Concept: Allows calculation of any one of the properties if the others are known.

5. Graham's Law of Effusion

  • Definition: The rate of effusion of a gas is inversely proportional to the square root of its molar mass.

  • Formula: Rate1/Rate2 = √(M2/M1)

  • Key Concept: Lighter gases effuse faster than heavier gases.

6. Dalton's Law of Partial Pressures

  • Definition: At constant volume, the pressure of a gas is directly proportional to its temperature in Kelvin.

  • Formula: P1/T1 = P2/T2

  • Key Concept: As temperature increases, pressure increases, and vice versa.

7. Gay-Lussac's Law

  • Definition: At constant volume, the pressure of a gas is directly proportional to its temperature in Kelvin.

  • Formula: P1/T1 = P2/T2

  • Key Concept: As temperature increases, pressure increases, and vice versa.

8. Combined Gas Law

  • Definition: Combines Boyle's, Charles's, and Gay-Lussac's laws.

  • Formula: (P1V1)/T1 = (P2V2)/T2

  • Key Concept: Used when a sample of gas experiences changes in pressure, volume, and temperature.

7. Gay-Lussac's Law

7. Gay-Lussac's Law

  • Definition: At constant volume, the pressure of a gas is directly proportional to its temperature in Kelvin.

  • Formula: P1/T1 = P2/T2

  • Key Concept: As temperature increases, pressure increases, and vice versa.