Quiz 1 - Properties of Gases | Properties of Gases

Gas volume changes significantly with pressure AND temperature

At constant volume: P and T are directly proportional ⇒ $\frac{{\mathrm{P}}_1}{{\mathrm{T}}_1} =<span\; style="font-family:\; Sailec,\; "Helvetica\; Neue",\; Helvetica,\; Arial,\; sans-serif;"> </span>\frac{{\mathrm{P}}_2}{{\mathrm{T}}_2}$  = cste

In the ideal-gas equation, the pressure is in Pa and the volume in m³

Ideal-gas equation: PV = nRT ⇒ If P increases, V decreases and vice versa (P and V are inversely proportional to each other)

Better conditions for a gas to behave like an ideal gas: monoatomic gas, low pressure, high temperature

In the kinetic theory of gases, the molecules exert no attractive or repulsive forces on each other except during collisions ⇒ between collisions they move in straight lines.

The Van der Waals equation for real gases is (P + ) (V − b) = nRT, where a and b are constants that correct for intermolecular forces and the volume occupied by gas molecules, respectively.

The mean free path is the average distance that a gas molecule travels before it collides with another molecule.

Graham's Law states that the rate of effusion is inversely proportional to the square root of the molar mass of the gas. Hydrogen has the lowest molar mass, so it will effuse the fastest.

Dalton's Law states that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of each individual gas.