Review For Homework For Kinetics And Equilibrium

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Answer the following question either incomplete sentences (including any graphs when needed) or showing all work (including sig fig, units,etc)



1. What is the name of the theory (and give a one sentence explanation) that all of kinetics are based on? For my class, what two words must be in all answers (except reaction mechanism problems) and what two factors determines it.
















2. Explain why increasing the temperature of a reaction increases the rate of the reaction. Please include in your discussion the appropriate kinetic energy diagram (make sure to discuss the graph and not simply show the graph). Remember, graph/diagram/figure do not say anything, you must explain the diagram.



















3. One mechanism for the destruction of ozone (O3) in the upper atmosphere is

O3(g) + NO(g) --> NO2(g) + O2(g) Slow
NO2(g) + O(g) --> NO(g) + O2(g) Fast
__________________________________________________________________________________________
O3(g) + O(g) ---> 2 O2(g) Overall Reaction

(It may be easier to answer a & b if you first thing about the definitions)
a. Which species are catalysts.
b. Which species are intermediate.
c. I did some experiments and found that if I increased the concentration of O3, the rate of reaction increased and if I increased the concentration of O(g), the rate of reaction also would increase. Does the above reaction mechansim support this data or not? Explain.














4. a) What is the main difference between an irreversible and reversible reaction? (Hint: at infinite time, what is in your bucket?)
b) On a graph of concentration ([ ]) vs. time, show where equilibrium occurs and explain it in macroscopic term (looking at the overall bucket) and microscopic term (following one particle).



























5. What are the two ways that you can write the equilibrium constant expression (hint, qualititively & quantatively). The equilibrium constant is important because it is considered a predictive quantity (i.e. it helps to explain what is going to happen). Please explain what this means including what the three difference ranges of the K value mean.























6. Using the theory of all systems want to go to the lowest energy state, explain your answer to question 4 of this homework (a diagram will help). Is it possible to initially put only product in your bucket, and why can you or can't you?(2013-2014 Do not Do this Question



























7. In your own words, please provide an outline on how to calculate equilibrium problems. Do not use complete sentences, just phrase and make sure to separate the procedures for doing the math for the three major types of equilibrium problems.






















8. The reaction below reaches equilibrium in a 0.25L container.
2 SO3(g) + 1 CO2(g) <==> 1 CS2(g) + 4 O2(g)

An analysis of the equilibrium mixture gives the following results:
SO3(g) 0.053mol, CO2(g) 0.106mol, CS2(g) 0.047mol, O2(g) 0.025mol.
Calculate K for this reaction (also give units of K).



















9. At a particular temperature, 8.0mol NO2 is placed in a 1.0L container and the NO2 dissociates by the reaction:
2 NO2(g) <==> 2 NO(g) + 1 O2(g)

At equilibrium, the concentration of NO is 2.0M. Calculate K for this reaction.



















2013 - 2014 DO NOT DO QUESTIONS BELOW

10. At a given temperature, the reaction below has a K = 2.50
1 SO2(g) + 1 NO2(g) <==> 1 SO3(g) + NO(g)

If all four gases had an initial concentration of 1.00M, calculate the equilibrium concentration of all species.

(For 2011-2012 Can Not Do This Problem)


















11. The industrial production of ammonia is described by this reversible reaction
1 N2(g) + 3 H2(g) <==> 2 NH3(g) + Energy

Using the 4 part explanation for how Le Chatlier's Principle would explain how the system would be affected by the following stresses:

a.Stress: Addition of heat (increase temp)

How rxn tries to remove stress: _________________________________________________

Circle: Make more product or more reactant

Circle: Favoring: Forward rxn or Backward rxn

Circle: Shift Equilibrium to: Left(more reactant) or Right (more product)




b. Stress: Removal of NH3

How rxn tries to remove stress: _________________________________________________

Circle: Make more product or more reactant

Circle: Favoring: Forward rxn or Backward rxn

Circle: Shift Equilibrium to: Left(more reactant) or Right (more product)



c. Strees: Decrease of pressure

How rxn tries to remove stress: _________________________________________________

Circle: Make more product or more reactant

Circle: Favoring: Forward rxn or Backward rxn

Circle: Shift Equilibrium to: Left(more reactant) or Right (more product)



d. Stress: Addition of a catalyst

How rxn tries to remove stress: _________________________________________________

Circle: Make more product or more reactant

Circle: Favoring: Forward rxn or Backward rxn

Circle: Shift Equilibrium to: Left(more reactant) or Right (more product)


























Answers
Question 1 : Collision theory, Effective collisions (EC), Eac and 3D orientation

Question 2 : Increase Temp (increase energy per particle), more particles with Eac (in KE graph, area under curve etc), make more EC, making more product per time increase rate of reaction. (With need to make graph and explain in more detail).

Question 3 : a) NO is catalyst b) NO2 is intermediate, c) if increase means significant increase, mechanism does not support it since O is a reactant in the fast step so it would not significantly increase rate.

Question 4: a) In reversible rxn bucket, have all species present; irreversible rxn bucket only have products. b)On graph, it is where concentration line straighten out.

Question 5 : General with K = [Product]E / [Reactant]E and Specific to the chemical rxn, see notes.
K>1 indicates at equilibrium, more P than R, K<1 indicates at equil, more R than P and K=1 similar amounts of P and R

Question 6: Do not do

Question 7 : Your own words

Question 8 : K = 9.89E-4 M2

Question 9 : K = 0.11 M

Question 10 : [SO3]E = 1.22M, [NO]E = 1.22M, [SO2]E = 0.776M, [NO2]E = 0.776M

Question 11a:Stress;Increase Temp (E), system consume E, Reactants, Backward (endo) rxn, shift equil L
Question 11b:Stress; Removal NH3, system to make NH3, Product, forward rxn, shift equil R

Question 11c: Stress; Decrease P, system increase P, Reactants (since 2 product particles become 4 reactant particle increasing # of particles), backward rxn, shift equil to L

Question 11d; Stress; addition of catalysts, equilibrium will not change since catalyst do not effect equilibrium (only increase rate of reaction, forward and back are increased equally)


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