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Terms in PVm = RT

P - Pressure

Vm - Molar Volume (v/n)

R - Universal Gas Constant (8.314 J/molK)

T - Temperature

Vm - Molar Volume (v/n)

R - Universal Gas Constant (8.314 J/molK)

T - Temperature

Dalton's Law

Total pressure in a vessel equals sum of pressures that the gases exert in other vessels.

Amagat's Law

At constant T and P total volume of a gas is equal to volume of each component of the gas.

All gasses act ideal...

At very low P, very high T

Partial Pressure of each component of a gas

Pi = YiP, where Yi is mol fraction of that gas

Average Molar Mass of Gas

Sum of YiMi, where Yi is mol fraction of component and Mi is molar mass of component

Balance Equation

Accumulation = Input + Generation - Output (Input = Output when CV, no chemical reaction)

Diameter of a Molecule (1Å)

10 x 10⁻¹⁰m

Ek = m/2 c²

m - mass

c² - x+y+z velocity squared

c² - x+y+z velocity squared

√(c²) = √(3RT/M)

Root Mean Square Velocity (average velocity of gas particles)

R - Universal Gas Constant

T - Temperature

M - Molar Mass

R - Universal Gas Constant

T - Temperature

M - Molar Mass

Boltzmann Constant

k = R/Na = 1.3805x10⁻²³ J/K

Cmp < C < √(C²)

Always check: Most probably velocity < Mean Velocity < Root Mean Square Velocity

c = √(8RT/∏M)

Mean Velocity (speed)

R - Universal Gas Constant

M - Molar Mass

R - Universal Gas Constant

M - Molar Mass

Cmp = root(2RT/M)

Most probable velocity (speed)

Cv = (∂Q/∂T)v = (3/2) R

Constant Volume Heat Capacity

Heat added at constant volume

Heat added at constant volume

Cp = (∂Q/∂T)p = (5/2)R

Constant Pressure Heat Capacity

Heat add at constant pressure

Heat add at constant pressure

Cp Cv relationship for ideal gases

Cp = Cv + R

Cp/Cv = 1.667

Cp/Cv = 1.667

λ = (kT) / (∏σ²P√2)

Mean Free Path (λ) - Average distance molecule travels between two successive collisions

σ - collision diameter

k - Boltzmann Constant (1.3805x10⁻²³ J/K or (kg.m²/s²)/K

σ - collision diameter

k - Boltzmann Constant (1.3805x10⁻²³ J/K or (kg.m²/s²)/K

σ

Collision Diameter - Distance between centers of two colliding molecules at which point repulsive forces become large enough to reverse motion.

λ = μ/P √(∏RT/2M)

Mean Free Path (λ) - Average distance molecule travels between two successive collisions

μ - Viscosity

μ - Viscosity

μ = (M/Na ∏σ²) √(RT/∏M)

Viscosity

Na - Avogadro's Number (6.022x10²³ mol⁻¹)

Na - Avogadro's Number (6.022x10²³ mol⁻¹)

Na

Avogadro's Number

6.022x10²³ mol⁻¹

6.022x10²³ mol⁻¹

μ

Viscosity

λ

Mean Free Path (λ) - Average distance molecule travels between two successive collisions

ρn

Number Density - Molecules/unit volume

ρn = Na/Vm

ρn = P/(KT)

ρn = Na/Vm

ρn = P/(KT)

λ = 1 / (∏σ²√2)(ρn)

Mean Free Path (λ) - Average distance molecule travels between two successive collisions

ρn - Number Density

σ - Collision Diameter

ρn - Number Density

σ - Collision Diameter

PVm = Na k T

Ideal gas equation for a mole of ideal gas

∂ = (kT/P)¹/³

Mean distance between molecules

∂³ = volume occupied by a molecule

∂³ = volume occupied by a molecule

∂ = (1/ρn)¹/³

Mean distance between molecules

∂³ = volume occupied by a molecule

∂³ = volume occupied by a molecule

(ρn c)/4

Collisions/unit area

Flux

Amount of molecules/unit area/unit time

molecules/m² s

molecules/m² s

Viscosity

μ - The resistance to deformation or resistance to flow exhibited by a fluid.

Measure of transfer of momentum of a substance.

μ is a constant coefficient of viscosity for a substance.

Viscosity is ONLY a function of T, not P!

Measure of transfer of momentum of a substance.

μ is a constant coefficient of viscosity for a substance.

Viscosity is ONLY a function of T, not P!

Thermal Conductivity

Correlate the transport of heat energy of a substance

Diffusivity

Correlate the transport of mass within a substance

κ = μ(Cv/M)

Thermal conductivity

κ - Proportionality constant for thermal conductivity

Cv - Molar heat capacity

μ - Viscosity

κ - Proportionality constant for thermal conductivity

Cv - Molar heat capacity

μ - Viscosity

Dab = [(RT)/(P Na ∏ σ²)]√(RT/∏M)

Molecular Diffusion - Diffusivity

Net transport of a substance from one region to another within a single phase, in absence of bulk movement or agitation.

Dab - Diffusion Coefficient

σ - Collision Diameter

Net transport of a substance from one region to another within a single phase, in absence of bulk movement or agitation.

Dab - Diffusion Coefficient

σ - Collision Diameter

Number Density

ρn = (P Na)/(RT)

Na implied at 1 molecule if not stated

Na implied at 1 molecule if not stated

Mass of molecule

M/Na

M - molar mass

Na - Avagadro's Number

M - molar mass

Na - Avagadro's Number