Chemical Kinetics, EQ, And Thermochemistry

General Chemi Stry Cha
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Name all the reaction orders

Zero order
First order
Second order
Higher order
Mixed order

mol solute/L of solution
Zero-Order reactions

has a constant rate, independent of the reactants concentration.
r = k
What are the units of k?
Radioactive decay

[At] = [Ao] e-kt
[Ao] is the initial concentration of A
[At] is the concentration of A at time T
k is the rate constant
t is elapsed time
products < reactants

exothermic (-)
products > reactants
endothermic (+)
What are the factors affecting reaction rate?

reactant concentration
Equilibrium Expression
Products / Reactants
What type of states don't appear in the equilibrium constant?
liquids and solids
Le Chatelier's principle
A system to which stress is applied tends to change to relieve the applied stress.

A + B ---> C + D
If more A is added
Then the equilibrium will switch to the right
Change in pressure and volume
Inverse to one another. If pressure increases, volume will decrease. If pressure or volume is increased the equilibrium will go to the least amount of moles.
Change in Temperature

In an exothermic reaction:
If the temperature increases the EQ will go to the left. If the temperature decreases the EQ will go to the right.
Equation to determine the decay constant
t1/2 = 0.693 / k
What types of systems exist

isolate, closed, and open
isolated- neither energy or matter can be exchanged
closed- only energy can be exchanged
open- everything can b exchanged
occurs when the temperature of the system remains constant
occurs when no heat exchange occurs
when the pressure of the system remains constant
Heat is measured in?
calories (cal) or Joules (J)
Measuring calorimetry or heat changes
q = mc(delta)T
delta H = H of products - H of reactants
Hess's Law
States that enthalpies of reactions are additive.
Entropy is the measure of?
Disorder or randomness. The greater the entropy the more disorder.
What's the second law of thermodynamics
all spontaneous process proceed such that the entropy of the system plus its surrounding increases
Gibbs Free Energy equation
deltaG = deltaH - TdeltaS
If delta G is negative
the reaction is spontaneous

delta H delta S
- +
+ -
+ +
- -

spontaneous all the time
nonspontaneous all the time
spontaneous at high T
spontaneous at low T
ΔG₀ = - R·T·ln(Keq)
ΔG₀ + R·T·ln Q

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