Ideal Gases Flashcards
What is an ideal gas?
A gas with no intermolecular potential energy; internal energy is only kinetic energy.
What is Avogadro’s Constant?
The number of atoms in 12g of carbon-12.
What is a mole?
The amount of substance containing as many particles as in 12g of carbon-12.
What is the ideal gas equation?
pV = nRT
What does R represent in the ideal gas equation?
Molar gas constant = 8.31 J·K⁻¹·mol⁻¹
What are the conditions for the ideal gas equation to apply?
Fixed amount of ideal gas.
What does Boyle’s Law state?
P ∝ 1/V → pV = constant
What does Charles’s Law state?
V ∝ T → V/T = constant
What does the Pressure Law state?
P ∝ T → P/T = constant
What is the combined gas law?
(P₁V₁)/T₁ = (P₂V₂)/T₂
How do you calculate moles from mass?
Moles = mass / molar mass
What is the alternate ideal gas equation using particles?
pV = NkT
What is Boltzmann’s Constant (k)?
k = R / NA = 1.38 × 10⁻²³ J·K⁻¹
What causes gas pressure on container walls?
Molecules hitting walls and rebounding; change in momentum creates force
What is Brownian motion evidence of?
Random movement of gas particles
What are basic assumptions of kinetic theory?
Many particles, negligible forces, negligible volume, elastic collisions, no collision time, KE ∝ T.
What is the mean square velocity <c²>?
Average of the squares of molecular velocities.
What is root mean square (rms) speed?
The square root of the mean square velocity.
What is the pressure formula from kinetic theory?
pV = (1/3)Nm<c²>
What is the pressure-density formula?
p = (1/3)ρ<c²>
How is kinetic energy related to temperature (method 1)?
(3/2)kT = (1/2)m<c²> → Ek = (3/2)kT
How is kinetic energy related to temperature (method 2)?
Deriving from NkT = (1/3)Nm<c²>
What is the relation between temperature and kinetic energy?
T ∝ Ek
How do you find the number of particles in a gas sample?
N = n × NA
