# Flashcard Set Preview

Side ASide B

Name all the reaction orders

Zero order
First order
Second order
Higher order
Mixed order

M

Molarity
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?

Msec-1

Radioactive decay

[A

_{t}] = [A_{o}] e-kt [A_{o}] is the initial concentration of A [A_{t}] is the concentration of A at time T k is the rate constant t is elapsed...
products < reactants

exothermic (-)

products > reactants

endothermic (+)

What are the factors affecting reaction rate?

reactant concentration
temperature
medium
catalyst

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

t

_{1/2}= 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

isothermal

occurs when the temperature of the system remains constant

adiabatic

occurs when no heat exchange occurs

isobaric

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

Enthalpy

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

ΔG₀ = - R·T·ln(Keq)

ΔG

ΔG₀ + R·T·ln Q