Test 2 Pchem
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Test 2 Pchem
Entropy formula for adiabatic isothermal cycle (carnot)
Energy over temperatrure
Is entropy a state function
Is Pressrua state function
Is Volume a state funciton
Is Temperature a state function
Is Internal Energy a state function
Is work a state function
Is enthalpy a state function
What do state functions equal in a carnot cycle
What is a clausius inequallity
Statement that entropy of an irreversible cycle is less than that of a reversible cycle.
What is always true of entropy of an irreversible cycle?
Alays less than 0
Clausius statement of entropy
The universal entropy always moves towards a maximum
Microscopic entropy deffinition
Entropy is a measure of disorder. The more ways molecules can move and be arranged, the higher the entropy
How does entropy affect temperature
Higher temperature leads to higher entropy
What is entropy of melting?
What is entropy change of boiling
What can always be said of the sign on entropy of a state change?
If state change is to more mobile form, is positive, if to less mobile form is negative.
Enthalpy of transition formula
Change in entropy at constant volume formula?
Change of entropy at constant volume formula
What is change in ewntropy formula when both temp and volume change
Entropy of mixing gas in terms of mol fractions?
When is entropy 0 when mixing gasses?
When there is no change in volume
Entropy of mixing gasses in volume term formula?
Entropy phase change order of operations.
1) Heat or cool initial phase to temperature of phase change, calculate entropy
2) Calcualte entropy of phase changte
3) Heat or cool final phase to final temperature, calcuate entropy
4) sum entropies
Entropy changes become zero at absolute zero
Absolute entropy of a reaction formula?
WHat is the entropy condition of equilibrium and when will this occur? Two formulas and deffinition
On a graph of entropy, we reach equilibrium when the composition of system is such to maximize entropy.
What can be said of relationship between entropy of surrounding and change of energy in system?
What must happen to entropy for a process to be spontaneous?
The overall entropy must increase.
What is Gibbs free energy in relation to entropy?
What is gibbbs requirement for equilibrium at constant Temp and PRessure?
Which direction will a reaction move as determined by gibbs?
In which ever direction minimizes gibbs free energy
Is Gibbs a state function?
What is the deffinition of helmholtz energy (A)?
When will we reach equilibrium according to helmholtz?
When dA = dU-TdS = 0
What does a negative gibbs tell us a bout a reaction?
That it will happen spontaneously.
What is an exergonic compound?
One whose gibbs free energy is negative and will form spontaneously.
What is an endergonic compound
One whose gibbs free energy is Positive and will not form spontaneously.
Gibbs in terms of volume and pressure?
Internal energy change for process involving only PV work (Maxwell)?
du = -PdV + TdS
Measure of how far from ideality a gas is.
Relationship betweeen work and helmholtz (a)
Relationship between gibbs and work
What is the Equilibrium constant ( K)?
If stoichometetric equation is:
Products -> reactants
aA+bB = cC + dD
How does equilibrium constant (k) related to gibbs?
What are the three equilibrium constants and what differentiates tehm?
= dimensionless constant
= dimensionless form of K if units are in pressure (bar)
is the dimensoinless form if units are in concentration (mol/L)
What happens to reaction rates at equilibrium?
Forward and backward rates proceed at same rate.
What energy condition indicates equilibrium?
Gibbs and helmholtz are minimized.
Chemical Potential: Symbol, deffinition and Formula
is the molar gibbs energy of a reaction at pressure other than 1 bar (not in standard state).
Gibbs energy chemical potential form when not at equilibrium
What is \
What be da formula for K
What is relation between k
What is k
Equilibrium constyant in mol fractions.
What is K
iun terms of K
how much of a substance will dissolve.
What is a?
a is the shorthand for chemical activity in a sollution.
This is when we have a reaction in which reactants are in different phase.
We treat pure solids and liquids as having a concentration of 1 and an activity coefficient of 1. They thus drop out of K.
Mix of reactions.
If there be multiple reactions, then:
Van Hoft Equation for effect of temperature on equilibrium constant?
This equation maps the effect of temperature on equilibrium constants.
integrating this yeilds:
Temperature dependence of equilibrium constant for ideal gases?