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Quiz Reaction Rates and Equilibrium
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What are the units for a reaction rate?
M/s, molarity per second, concentration per second
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What is the highest energy stage of a reaction
called?
transition state or activated complex
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How does a catalyst speed up a reaction?
Lowers activation energy barrier
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When reacting molecules collide with each other,
do they always form a reaction?
No, improper orientation, not enough KE
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What is a calorie or joule?
Unit of heat (q)
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What are the four factors we discussed that
affect the rate of reaction?
Temperature, concentration, particle size, and
use of catalyst
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What does an inhibitor do?
Interferes with the action of a catalyst
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At equilibrium, what can you say about reactants
and products?
The rates of production of both are equal.
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What does the double arrow mean in chemistry?
There is a forward and reverse reaction
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If a stress is applied to a system in dynamic
equilibrium, the system changes in a way that
relieves the stress, is known as _________.
Le Chateliers Principle
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According to Le Chateliers Principle, if you
remove products from a reaction at equilibrium,
what will happen to the reactants?
The reactants will react more to offset the loss
of products, thus becoming lower themselves
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True or False. If you have more gas molecules on
the left-side of a reaction, and you increase the
pressure, the equilibrium will shift to the right.
True
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True or False. If Keq 1 x 10-5, then products
are favored.
False
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Solve the Keq expression for the following
reaction.
Mg(s) 2HCl(aq) ?? MgCl2(aq) H2(g)
Keq MgCl2H2/HCl2
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Write an expression for the solubility product
constant, Ksp, for the following dissolving
process.
NaCl(s) ?? Na(aq) Cl-(aq)
Ksp NaCl-
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What is the equation for Gibbs Free Energy?
DG DH-TDS
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What is DS and what does it measure?
Entropy, it measures disorder In a system
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What is DH and what does it measure?
Enthalpy, it measures the heat in a reaction
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If the heat of a reaction, DH, is -56.7 kJ, what
can you say about the reaction?
Exothermic, gives off heat when reactants are
combined
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If you take a solid and liquid, and mix them to
produce a gas, what can you say about the
reaction in terms of chaos theory?
DS is positive Entropy obviously increased
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What can you say about a reaction that has DG?
Nonspontaneous
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What three variables can tell you whether a
reaction will occur on its own or need outside
help?
Enthalpy, DH Entropy, DS Temperature of system
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If the DH of a reaction is positive then the
reaction is _______ .
endothermic
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What is the enthalpy change in a chemical
reaction known as?
Heat of reaction, DH
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Can you do the following?
-Write out a Keq expression when given a random
reaction -Then plug in given concentration values
to actually calculate Keq. - Then interpret what
the Keq value actually means?
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Can you do the following?
-If you are given Ksp, can you calculate
individual ion concentrations?