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Quiz 2 will cover the following:
<br>
<br>
Chapter 14 (14.3-14.7), Chapter 15 (15.1-15.7)
<br>
<br>
There is some overlap with quiz 1 for chapter 14.
<br>
<br>
<br>
Section 14.3
<br>
<br>
Know how to obtain a rate from data and how to use rate data to
determine the
<br>
rate law using the method of initial rates. This is shown in the
book in
<br>
sample ex 14.6 (and the practice exercise) and my notes. You really
need to
<br>
learn how to do this using the second example I used in lecture (the
long
<br>
one). If you don't you will have problems with some of the
end-of-chapter
<br>
exercises (especially the last one for section 14.3).
<br>
<br>
Remember, rate laws can depend on concentration of reactants,
products and
<br>
catalysts. The orders of substances in the rate law can be whole
numbers,
<br>
simple fractions, negative (usually seen for products and
inhibitors). To get
<br>
the overall order you simply add the orders for everything in the
rate law.
<br>
Also, remember in general you can't write the rate law from the
balanced
<br>
chemical equation. It must be determined experimentally. The ONLY
time you can
<br>
write a rate law from a balanced eqn is if you know the reaction is
an
<br>
elementary reaction (a single-step mechanism) and you don't know
this by
<br>
simply looking at the reaction.
<br>
<br>
Section 14.4
<br>
<br>
Know what an integrated rate equation is for zero-order, 1st-order
and
<br>
2nd-order reactions and be able to use them. Know what the half-life
is for
<br>
zero-order, 1st-order and 2nd-order reactions. This is in section
14.4. The
<br>
equations for zero-order are in the notes and there are a couple of
questions
<br>
in the chapter 14 handouts passed out in class and on the web (see
"notes"
<br>
link) about zero and 2nd order. Be able to do the special problem
passed out
<br>
in class and sent via e-mail.
<br>
<br>
Section 14.5:
<br>
<br>
Understand the relationship between temp., activation energy (Ea)
and rate
<br>
constant (Arrhenus eqn.) and the rate of the reaction. Understand
how all
<br>
this relates to collision theory and transition state theory.
<br>
<br>
Section 14.6:
<br>
<br>
Understand mechanisms and how to obtain a rate law from a mechanism,
<br>
rate laws for elementary reactions, recognize intermediates,
<br>
and what molecularity means.
<br>
<br>
Remember, steps in a mechanism are always written as elementary
processes,
<br>
which means the rate law for a step can be written from the balanced
eqn
<br>
for that step. This is the ONLY time you can write the rate law
from a
<br>
balanced eqn.
<br>
<br>
Section 14.7:
<br>
<br>
Know what catalysts are and the four common characteristics of
catalysts,
<br>
homogeneous and heterogeneous catalysis, how catalysts work and be
able
<br>
to recognize a substance as a catalyst or intermediate in a
mechanism. Know
<br>
how a catalyst affects rate and how this can be seen using the
Arrhenus eqn.
<br>
<br>
You can find the handouts mentioned above at
<br>
<br>
<a
href="http://www.chemistry.ohio-state.edu/%7Erzellmer/chem1220/notes/ch14houts.pdf"><b>Chapter
14 - Chemical Kinetics - Handouts</b> </a> <br>
<br>
You should be able do to homework problems 14.9-14.16, 14.53-14.96,
<br>
14.110-14.118, 14.120-14.126
<br>
<br>
For those of you using the 11th edition the quiz covers sections
14.5-14.7
<br>
and homework problems 14.7-14.12, 14.47-14.82, 14.94-14.103,
14.105-14.111
<br>
<br>
For those of you using the 10th edition the quiz covers sections
14.5-14.7
<br>
and homework problems 14.6-14.10, 14.45-14.80, 14.90-14.97,
14.99-14.105
<br>
<br>
Don't forget the extra homework problems handed out in class. They
can also
<br>
be found on the web at the Notes link (see above) or Homework link
where you
<br>
will also find the solutions,
<br>
<br>
<a
href="http://www.chemistry.ohio-state.edu/%7Erzellmer/chem1220/homewk/ch14hmwk_add.pdf"><b>CH
14 - Kinetics, Extra Problems and Solutions</b></a><br>
<br>
<br>
Sections 15.1-15.6:
<br>
<br>
You need to understand how to set up an expression for the
equilibrium
<br>
constant, K and how to use it. Understand how to set up K for
<br>
heterogeneous equilibria (when you have pure solids and liquids
involved
<br>
in the equilibrium). What appears in an equilibrium constant (gases
and
<br>
solutes in solution but not pure solids or liquids)?
<br>
<br>
What does the magnitude of K tell you? Does the reaction go to
completion
<br>
and by how much (mostly products or "essentially only" products)?
Does the
<br>
reaction "not occur to any great extent" and how little reaction
occurs
<br>
(mostly reactants or "essentially only" reactants)? Are there
appreciable
<br>
amounts of reactants and products at equilibrium?
<br>
<br>
Remember K depends on the form of the balanced equation and you can
<br>
relate the K for one form of the balanced equation to another
<br>
(e.g. K_rev = 1/K_for or K_for<sup class="moz-txt-sup"><span
style="display:inline-block;width:0;height:0;overflow:hidden">^</span>-1</sup>).
<br>
Know the relationship between equilibrium constants when you add
several
<br>
balanced equations to get a new balanced equation.
<br>
<br>
Know how to use an equilibrium (ICE) table and use it to determine K
from
<br>
equilibrium concentrations.
<br>
<br>
Know how to relate Kp and Kc.
<br>
<br>
Understand the reaction quotient, Q, and how you use it with K to
predict
<br>
whether the reaction is at equilibrium or not and if not which
direction
<br>
does it proceed to reach equilibrium.
<br>
<br>
Know how to use an ICE table to calculate equilibrium conc. starting
with
<br>
initial conc. and the equilibrium constant, K.
<br>
<br>
On the quiz, if you need to use an ICE table, you MUST SHOW the WORK
and the
<br>
ICE table. When making any assumptions you should show that your
<br>
assumptions are okay (less than 5% error). If the percent error is
greater
<br>
than 5%, you need to solve the problem in a more exacting way (solve
a
<br>
quadratic, method of successive approximations, etc.). You
<br>
must show this work. If you don't, you will not get full credit.
<br>
<br>
Section 15.7: Le Chatelier's Principle
<br>
<br>
Understand how changing conc. shifts a reaction
<br>
(AWAY from ADDED, TOWARD REMOVED). Remember adding or<br>
removing (small
amounts, but not all) of a pure solid or pure liquid will<br>
not shift a
reaction. Removing all of a pure solid or pure liquid will shift
the
<br>
reaction (toward the removed substance - you have to have some of
the
<br>
solid or liquid to be at equilibrium when they are present in the
rxn).
<br>
Adding or removing a pure liquid which is also the solvent will
cause a
<br>
shift due to an indirect effect (e.g. adding solvent decreases the
conc. of
<br>
the solutes causing the reaction to shift). I discussed this using
exp 5 (EQL)<br>
in lecture today. Conc. changes do NOT affect the numerical value
of K.
<br>
<br>
Know how changing pressure (due to volume changes) effects a
reaction.
<br>
Increasing pressure (by reducing the volume) shifts the reaction
toward
<br>
fewer moles of gase. Decreasing pressure (by inc. the volume)
shifts
<br>
the reaction toward more moles of gas.
<br>
Pressure changes do NOT affect the numerical value of K.
<br>
<br>
Also, know how changing temperature shifts a reaction AND changes
the numerical
<br>
value of the equilibrium constant, K (changing conc. and pressures
do not affect
<br>
the numerical value of K).
<br>
<br>
You should be able do to homework problems 15.1-15.100
<br>
<br>
For those of you using the 11th edition the quiz covers sections
15.1-15.7 and
<br>
homework problems 15.1-15.88
<br>
<br>
For those of you using the 10th edition the quiz covers sections
15.1-15.7 and
<br>
homework problems 15.1-15.85
<br>
<br>
<br>
Don't forget the extra homework problems. They can be found on the
web at
<br>
the Homework link on the class web page (CH 15 - Extra ICE Table
Problems and
<br>
Solutions),
<br>
<br>
<a
href="http://www.chemistry.ohio-state.edu/%7Erzellmer/chem1220/homewk/ch15_extra_problems.pdf"><b>CH
15 - Extra ICE Table Problems and Solutions</b> </a><br>
<br>
<br>
Dr. Zellmer
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