Gas Phase Flashcards
What is an ideal gas?
Hypothetical gas with molecules that have NO intermolecular forces and occupy NO volume
When does an gas deviate from the ideal gas laws?
At high pressure and low temp
What is the ideal gas law?
PV = nRT
What is the ideal gas constant?
R = 8.2 . 10^-2
What is the density of a gas equal to?
density = P.M / RT = m/V
What is the combined gas law?
P1V1/T1 = P1V2/T2
What is the volume of a mole of gas at STP?
22.4 L
How does doubling the pressure affect the volume of a gas?
Halve the volume
In what unit is temp is gas laws?
Kelvin
What is Boyle’s law?
P1V1 = P2V2
What is Charles’ Law?
V1/T1 = V2/T2
What is Avogadro’s principle?
n1/V1 = n2/V2
What is Gay-Lussac’s Law?
P1/T1 = P2/T2
What are the 2 equations for Dalton’s law?
Pt = PA + PB +... PA = Xa . Pt = moles of A/total moles x Pt
What is Henry’s Law? What does it mean?
kh = [A1]/P1 = [A2]/P2 OR [A] = Pa . kh
The solubility of a gas will increase with increasing partial pressure
[A] = concentration in solution
What is the average kinetic energy of gas particles?
KE = 3/2 . kb . T
What is Boltzmann constant?
kb = 1.4 x 10^-23
What is the root mean squared speed? What does it represent?
urms = squaroot of (3RT/M)
Represents the speed to which the average kinetic energy per particle corresponds
What is Graham’s Law of diffusion?
r1/r2 = squaroote of (M2/M1)
How is the volume of real gases compared to ideal gases at high P?
Less than
How is the volume of real gases compared to ideal gases at low P?
More than
How is the volume of real gases compared to ideal gases at high T?
More than
How is the volume of real gases compared to ideal gases at low T?
Less than
What is the Van der Waals equation of state? What is its purpose? What do a and b correct for?
(P+n^2a/V^2)(V-b) = nRT
Purpose: correct for deviations from ideality
a: corrects for intermolecular forces
b: corrects for volume of the molecules
