Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

22 Cards in this Set

  • Front
  • Back
Standard Temperature and Pressure
1 atm and 0 degrees C
mean free path
disance travelled by a gas molecule between collisions
properties of gas mixtures
-unlike liquids all gases will mix with each other regardless of polarity and form homogenous mixture
Kinetic Moleclar theory of an ideal gas
-gas molecules have zero volume
-gas molecules exert no forces other than repulsive forces due to collisions
-gas molecules make completely elastic collisions (KE is conserved)
-average KE of molecules is directly proportional to the temperature
Ideal Gas Law
Pressure Volume=#moles x universal gas constant x temp kelvin
-when gas expands in container it does work on surroundings and pressure decreases due to loss in KE and increase in volume and temperature decreases
-all gases that behave ideally will have same volume temperature, n, pressure
standard molar volume
22.4 liters
partial pressure of a gas
total pressure of the gaseous mixture times the mole fraction of the particular gas
-partial pressures of gases add up to total pressure (daltons law)
Average Translational KE formula for a gas
KEavg=3/2 RT
-just average for mole of gas, molecule chosen at random might have any KE
RMS velocities of two gases in homogenous mixture
v1/v2 = squareroot M2/ squareroot M1
-notice v1 on top and m1 on bottom
-spreading of gas from high to low pressure through a pinhole
Rate1/Rate2= SquarerootM2/SquarerootM1
-similar to grahams law
-can be used to estimate diffuseion rates
Chemical Kinetics
how fast equillibrium will be achieved
-for a reaction need a collision and for a collision molecules need to reach activation energy
Arrhenius equation
-gives rate constant K
-greater the temperature greater the K
Equations for reaction rates
rate forward= k[A]^a[B]^b
k= rate constant for forward reactoin
A, B= molecules in equation
a,b= stoichiometric # of moles used as exponents in elementary reactions

total order of reaction = a + b
Recognizing reaction orders
first order reaction:
rate = k[A]
A decreases exponentially
graph of ln[A] vs. t = straight line with slope -k

Second Order
2A-> products rate=k[A]squared
plot 1/[A] gives straight line with slope k

third order
rate = k[A]cubed
plot 1/(2[A]squared) straight line with slope k
Reversible Reaction rates
slowest step = rate determining step
When slow step is second step
-assume first step reaches equillibrium
-for rate set forward reaction rate = to the reverse reaction rate for first step
ex. 1. NO + Br2 -> NOBr2
2. NOBr2 + NO -> 2NOBr

-increase rate of reaction
-lower Ea
-does not alter equillibrium
-concentration of catalysts are usually small compared to reactants and products, if it is large the rate changes little
heterogenous catalyst
-different phase than the reactants and products, usually solids
-reactant may physically adsorb (van der wals) or chemically adsorb (covalent bond) to surface of catalyst
-binding is exothermic
homogeneous catalyst
-same phase as reactants and products
-often aqueous acids or bases act as homogenous catalysts
Chemical Equilibrium
Forward rate=reverse rates
-no change in concentration of products
-net rate= 0
-point of greatest entropy
-set forward rates= to reverse rates

A+B-> C+D
rate forward=rate reverse

algebraic manipulation:
kf/kr= [C]c[D]d/[A]a[B]b

another name for kf/kr= Keq
:law of mass action
Keq= [C]c[D]d/[A]a[B]b
law of mass action
Keq= [C]c[D]d/[A]a[B]b
- kf is reciprocal for kr
-for Keq K is capitalized
-depends only on temperature
-solids or pure liquids are not used in equation
Reaction Quotient
-for reactions not at equillibrium

or products raised to coefficients/reactants raised to coeeficients

can have any positive value
-will always change towards Keq
Q=K : equillibrium
Q<K: increase products decrease reactants: rightward shift
Q>K increase reactants decrease products: leftward shift