Exam 3 Chapter 9

Question 1

diffusion

Answer 1

process by which molecules disperse in space in response to differences in concentration is called

net movement of species from high to low concentration areas takes place. In a closed environment, diffusion will ultimately result in equal concentrations of gas throughout

Question 2

rate of diffusion

Answer 2

the amount of gas passing through some area per unit time:

rate of diffusion=amount of gas passing through an area/unit of time

Question 3

effusion

Answer 3

the escape of gas molecules through a tiny hole such as a pinhole in a balloon into a vacuum

Question 4

Graham’s law of effusion

Answer 4

The rate of effusion of a gas is inversely proportional to the square root of the mass of its particles:

rate of effusion A/rate of effusion B =
sqrt(molar mass B) / sqrt(molar mass A)

Question 5

Root Mean Square Velocity of a Gas

Answer 5

Root Mean Square molecular speed (u)
speed of molecule with average kinetic energy

u = sqrt(3RT/M)
where M = molar mass in kg/mole
R, gas constant but uses different units (8.314 J/Kmole)
J = (kgm^2)/sec^2

Question 6

Van der Waal’s Equation

Answer 6

(P+n^2a/v^2)(v-nb)=nRT

where the values of a and b are experimentally determined

Question 7

Conditions of an Ideal Gas

Answer 7

Gases are most likely to behave ideally at LOW PRESSURES and HIGH TEMPERATURES because particles are moving faster and are farther apart

Question 8

When do gases deviate from ideal?

Answer 8

At HIGH PRESSURE and LOW TEMPERATURE

Question 9

Ideal Gas Law

Answer 9

PV = nRT

Question 10

Potential Energy

Answer 10

PE = mgh