Chemistry: Gay-Lussac's Law (Gas Laws) with 2 example problems

Introduction to Gay-Lussac's Law00:00:10

Temperature and pressure in a gas are directly proportional when other factors are constant. As temperature rises, gas particles move faster, increasing collisions with container walls and thus raising pressure. Conversely, cooling reduces particle speed, leading to fewer collisions and lower pressure.

Mathematical Formulation of Gay-Lussac's Law00:01:01

Joseph Louis Gay-Lussac and Guillaume Amontons established the law stating that when volume and amount of gas are constant, pressure (P) is directly proportional to temperature (T). This can be written as P ∝ T, or P = kT, where k is a proportionality constant. It can also be expressed as P/T = k, or for comparing two states, P1/T1 = P2/T2.

Example Problem 1: Calculating Pressure Change with Temperature00:02:08

A nitrogen gas canister at 2000 psi and 20°C is heated to 25°C. To find the new pressure, convert temperatures to Kelvin (293.15 K and 298.15 K). Using the formula P1/T1=P2/T2, P2 is calculated to be 2034 psi.

Example Problem 2: Calculating Temperature Change with Pressure00:03:18

A gas exerts 0.95 atm at 10°C. To find the temperature (in Celsius) at which it will exert 0.75 atm, convert 10°C to Kelvin (283.15 K). Using the formula, T2 is found to be 223.54 K, which converts to -49.6°C.

Other Gas Laws and Their Relationships00:04:33

Besides Gay-Lussac's Law, other gas laws include Charles's Law (temperature and volume), Boyle's Law (pressure and volume), and the Combined Gas Law (temperature, pressure, and volume). Avogadro's Law relates volume and the amount of gas. The Ideal Gas Law combines all four. All these laws require the amount of gas to remain constant.