Portage Learning / CHEM 104 / Module 1 to 6 Exams
Kinetics - ANSWER the study of rates of reactions and how they are influenced by
certain factors
Influences Reactions Rates - ANSWER Concentration, temperature, catalysts,
surface area
Temperature/Reaction Rate - ANSWER Increase, higher temperature provides
higher kinetic energy
Catalyst/Reaction Rate - ANSWER Increase, without being consumed
Surface Area/Reaction Rate - ANSWER Increase, increased surface area of
particles increases reaction rate because solids only react at their surfaces (grinding
solid into fine powder)
Concentration/Reaction Rate - ANSWER Increase, provides more reacting particles
to undergo reaction
Reaction Rate - ANSWER Increase in molar concentration of product per unit of time
or the decrease in molar concentration per unit of time
Reaction Rate Units - ANSWER moles per liter per second (mol/L*s)
Reaction Rate Equation - ANSWER Change in concentration/change in time
(products=positive, reactants=add negative sign)
Average Rate - ANSWER Determined by using initial and final concentrations and
initial and final times so that the result measures the rate over the entire reaction
Instantaneous Rate - ANSWER The change in concentration of reactants (or
products) divided by a very short period of time
Instantaneous Rate Decreases... - ANSWER Decreases, as reaction proceeds,
concentration of reactant becomes smaller due to consumption of reactants as
reaction takes place
Early Instantaneous Rate - ANSWER The change in concentration of reactants (or
products) divided by a very short period of time near the beginning of the reaction
Late Instantaneous Rate - ANSWER The change in concentration of reactants (or
products) divided by a very short period of time at the end of the reaction
Relative Values of Average Rate, Early Instantaneous Rate, and Late Instantaneous
Rate - ANSWER The early instantaneous rate will be greater (most reactant) than
, the late instantaneous rate or the average rate. The late instantaneous rate will be
smaller (less reactant) than the early instantaneous rate or the average rate.
Rate Law - ANSWER Mathematical equation that describes the dependence of the
reaction rate on the concentrations of some of the reactants
Equation for Rate Law - ANSWER rate = k [A]^x[B]^y
K - ANSWER rate constant
order with respect to a reactant - ANSWER Exponent of concentration in rate law
Zero Order - ANSWER Rate does not change if the concentration of that reactant is
changed (uncommon)
Experimentally - ANSWER How rate law must be determined
To Compare Rates - ANSWER rate1 / rate2 = k[A1]^x[B1}^y / k[A2]^x[B2]^y
First Order - ANSWER Rate is directly proportional to the concentration of one of the
reactants
Second Order - ANSWER Rate is proportional to the square of the concentration of
one of the reactants
Zero Order Reaction Rate Law & Units - ANSWER r = k, mol/L*s
First Order Reaction Rate Law & Units - ANSWER r = k [A], 1/sec
Second Order Reaction Rate Law & Units - ANSWER r = k [A]^2, L/mol*s
Half-Life Purpose - ANSWER Shows how reactant concentration varies over a
period over time
Given amount remaining other than 50% - ANSWER ln[A] - ln[A]0 = k t
Half-Life Definition - ANSWER The time required for one-half of a reactant to
undergo the reaction
Given 50% remaining - ANSWER ln (50) - ln (100) = k t 1/2
Given half life, use to find K, find T - ANSWER 0.693 = k t 1/2
Catalyst - ANSWER Substance that increases the rate of a chemical reaction without
itself being consumed; combines with reactants to form new intermediate that is able
to react more readily to form the product and regenerates the catalyst as the product
is formed
Effect of Solvent - ANSWER Reactions in solution allow the particles to come in
contact with one another more freely causing a higher rate of reaction
Kinetics - ANSWER the study of rates of reactions and how they are influenced by
certain factors
Influences Reactions Rates - ANSWER Concentration, temperature, catalysts,
surface area
Temperature/Reaction Rate - ANSWER Increase, higher temperature provides
higher kinetic energy
Catalyst/Reaction Rate - ANSWER Increase, without being consumed
Surface Area/Reaction Rate - ANSWER Increase, increased surface area of
particles increases reaction rate because solids only react at their surfaces (grinding
solid into fine powder)
Concentration/Reaction Rate - ANSWER Increase, provides more reacting particles
to undergo reaction
Reaction Rate - ANSWER Increase in molar concentration of product per unit of time
or the decrease in molar concentration per unit of time
Reaction Rate Units - ANSWER moles per liter per second (mol/L*s)
Reaction Rate Equation - ANSWER Change in concentration/change in time
(products=positive, reactants=add negative sign)
Average Rate - ANSWER Determined by using initial and final concentrations and
initial and final times so that the result measures the rate over the entire reaction
Instantaneous Rate - ANSWER The change in concentration of reactants (or
products) divided by a very short period of time
Instantaneous Rate Decreases... - ANSWER Decreases, as reaction proceeds,
concentration of reactant becomes smaller due to consumption of reactants as
reaction takes place
Early Instantaneous Rate - ANSWER The change in concentration of reactants (or
products) divided by a very short period of time near the beginning of the reaction
Late Instantaneous Rate - ANSWER The change in concentration of reactants (or
products) divided by a very short period of time at the end of the reaction
Relative Values of Average Rate, Early Instantaneous Rate, and Late Instantaneous
Rate - ANSWER The early instantaneous rate will be greater (most reactant) than
, the late instantaneous rate or the average rate. The late instantaneous rate will be
smaller (less reactant) than the early instantaneous rate or the average rate.
Rate Law - ANSWER Mathematical equation that describes the dependence of the
reaction rate on the concentrations of some of the reactants
Equation for Rate Law - ANSWER rate = k [A]^x[B]^y
K - ANSWER rate constant
order with respect to a reactant - ANSWER Exponent of concentration in rate law
Zero Order - ANSWER Rate does not change if the concentration of that reactant is
changed (uncommon)
Experimentally - ANSWER How rate law must be determined
To Compare Rates - ANSWER rate1 / rate2 = k[A1]^x[B1}^y / k[A2]^x[B2]^y
First Order - ANSWER Rate is directly proportional to the concentration of one of the
reactants
Second Order - ANSWER Rate is proportional to the square of the concentration of
one of the reactants
Zero Order Reaction Rate Law & Units - ANSWER r = k, mol/L*s
First Order Reaction Rate Law & Units - ANSWER r = k [A], 1/sec
Second Order Reaction Rate Law & Units - ANSWER r = k [A]^2, L/mol*s
Half-Life Purpose - ANSWER Shows how reactant concentration varies over a
period over time
Given amount remaining other than 50% - ANSWER ln[A] - ln[A]0 = k t
Half-Life Definition - ANSWER The time required for one-half of a reactant to
undergo the reaction
Given 50% remaining - ANSWER ln (50) - ln (100) = k t 1/2
Given half life, use to find K, find T - ANSWER 0.693 = k t 1/2
Catalyst - ANSWER Substance that increases the rate of a chemical reaction without
itself being consumed; combines with reactants to form new intermediate that is able
to react more readily to form the product and regenerates the catalyst as the product
is formed
Effect of Solvent - ANSWER Reactions in solution allow the particles to come in
contact with one another more freely causing a higher rate of reaction
