Gases

Question 1

What is the relationship of kinetic energy and temperature in kinetic-molecular theory?

Answer 1

U = 3/2kT

• they are directly prop.
• recall that: E = 1/2mv^2

Question 2

What are the two main assumptions of an Ideal Gas?

Answer 2

• gas has no size/volume

- gas has no attractive/repulsive forces (unless collide/elastic bouncing)

Question 3

What are the context that ideal gases like to behave ideally? What would then be the reasons that impair ideal behavior?

• what do these behaviors favor in terms of transition between states?

Answer 3

Ideal environment? - High temp, high volume, low pressure
- This favors liquid > gas

Non-ideal: Low temp, high pressure, low volume
- this favors gas > liquid

Question 4

What is classic Boyle’s Law?

How did you remember this law?

Answer 4

P1V1 = P2V2

• inverse relationship
• A boil gets bigger: larger volume and pressure inside

Question 5

What is classic Charle’s Law?

How did you remember this law?

Answer 5

V1/T1 = V2/T2 = k

• directly prop
• Charizard flames heat up gas and incr volume

Question 6

Avogadro’s Law?

How do you relate to volumes of different gases?

Answer 6

V/n = K

- same volume = same number of moles, assuming standard temp and presure

Question 7

At 1 atm and 273K, 1 mole of gas = _____?

What is 273K in C?

Answer 7

22. 4 L, called molar volume

- 273K = 0C

Question 8

What are standard thermodynamic conditions?

Answer 8

1 atp

25C = 298K

Question 9

Ideal gas law?

Answer 9

PV = nRT

Question 10

Real gas law equation? Van der waals?

What is the relationship to ideal calc?

Answer 10

(P+a/V^2m) (Vm - b) = RT

Vm = molar volume 
a = attraction, or repulsion
b = bra size, or size of particle

Normal conditions: Real < Ideal

• size of gas negligible
• attractive forces make volume smaller, less pressure on container

Extreme conditions: Real > ideal
- more presure and volume

Question 11

What does dalton’s law deal with?

Answer 11

partial pressures

Question 12

Graham’s law says what?

what equation does this connect to?

Answer 12

• smaller particles of gasses diffuse quicker
• Rate 1/Rate 2 = sq rt (molar mass 2/molar mass 1)
• relates to kinetic energy which relates 1/2mv^2 (derivation of square root)
• rate of diffusion is proportional to square root of reciprocal to molar mass, and thus also density

Question 13

Henry’s Law

Answer 13

C = kP

P = pressure
C = molar solubility: M/L
K = coefficient