Unit 3day 4 Flashcards
Write formula for partial pressure of blue
Using ideal gas law
Pblue = nblueRT/ V
Formula for total pressure of blue and green
Ptotal = Pblue + Pgreen
Write formula for P total
Using ideal gas law
P tot= ntotRT/ V
Write formula , for partial pressure of blue gas
Using mol fraction
Pblue = mole fraction(X) blue * Ptot
Write formula for mole fraction(X) of blue
Using moles
n blue/ n total
Equation for tank valve problems ( one has O2, one has N2)
PO2V1 = P’O2Vtot
PN2V2 = P’N2Vtot
Write the formula for total pressure for the tank valve problem
Gases are O2 and N2
Ptot= P’O2 + P’N2
Which ballon will have the most efficient reaction? Loudest bang?
The one with the most equal mole fraction to molecular formula (empirical)
Ideal gas descriptions
TEAR
Tiny- small discrete, far apart
Elastic/Energy - no energy lost or gained
Asexual- not attracted to each other
Random - molecules are constant, random , straight line motion, until they hit a wall
When ranking samples form highest to lowest average KE consider
ONLY consider temp
High temp has higher KE
Rank samples from highest to lowest velocity CONSIDER
consider both smallest particle(those will be faster) and temp, then use equation if different temp and contradicting different size particles
High temp small particles are faster
Equation for KE of gases with ideal gas law
KE = 3/2RT
What does R equal for KE formula with ideal gas law
R = 8.314 J/ mol K
Regular formula for KE
KE= 1/2m(v^2)
What are the units for the regular KE formulas
M (mass) is in Kg
v (velocity) is In m/s(meters per sec)
Which molecule is the lightest for probability density graphs
The one that has the flattest most spread out graphs, reaches the highest speed
Which molecule is the heaviest for probability density graphs
The molecule that has the highest peak and spreads the least over the x axis, lowest speeds
How does cold molecule graph look
Narrow distribution
How does hot molecule graph look
Wide distribution
Root mean square velocity , Vrms FORMULA
square root of (3RT/mm)
mm in kg/mol
What unit is the mass in for Vrms
Root mean square velocity
The molar mass of the element converted to Kg
Diffusion
Intermingling of gases due to their random motion
Effusion
Escape of gas particles through tiny holes
Write mole fraction(X) for blue using pressure
Pblue/P total
What units does Vrms equation give you
M/s
What size of particles effuse the best
Small particles effuse faster
If there’s a solid formed between 2 gases in a tube, where will the precipitate form close to?
Next to the gas aight he greater radius because it effuses slower
Grahams law
With velocity
Va/Vb = sq rt ( mmb/ mma)
When to use grahams law with velocity
When there’s the same temp and it’s the same molecule you’re comparing
Grahams law with temperature
Rate a/ rate b = sq rt(Ta/Tb)
When to use grahams law with temp(rates)
Diff temps same molecule
If Z is greater than 1, what are the interactions between gas particles
Repulsions
If Z is less than 1, what are the interactions between gas particles
Attractions
How do repulsion’s affect pressure
There are more collisions, higher pressure
How do attractions affect pressure
Less collisions, lower pressure
If the experimental pressure is greater than the ideal pressure what does that mean for the interactions between the gas particles
Repulsions
If the experimental pressure is LESS than the ideal pressure what does that mean for the interactions between the gas particles
Attractions
Gases behave most ideally at?
High temp and low pressure
Why do gases behave most ideally at high temp and low pressure
A lot of space, so less collisions, and ideally, gases are hot because they come as a result of boiling
What rules are not followed for real gases
T- Gases are not spaced far apart
A- gases are not asexual because they are not spaced far apart^, they are attracted to each other
What does Z equal for an ideal gas
1
What does Z less than 1, mean for IMFs?
High attraction forces if Z < 1 so strong IMFs
Hard square Model equation
P(V-nb)= nRT
What does v equal in hard square model ?
Volume of container
What does nb equal in hard square model
Space occupied by gas
Van der Waals Equation
(P +a(n^2)/(v^2))(v-nb) =nRT
What does a equal in van der waals equation
(Include units)
Attractive forces
Atm*L^2/ mol^2
What does b equal in hard square model
Include units
Size factor
L/mol
How do IMFS impact a in van der waals equation
Strong IMFS means large a
How does size impact b in hard square model
Large size(radius) means large b
When you think of diffusion think of
Mizing
When you think of effusion think of
Escape
The rate of effusion or diffusion equation
Va/vb = sq rt(mm a/mm b)
What do mol fractions and ONLY mol fractions add to?
1
What is the unit produced by the standard KE formula
Joules
What is v in KE = 1/2mv^2
Velocity
How many mL is 1cm^3
1 mL
