CHEM 104 MODULE 1 QUESTIONS AND
ANSWERS
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
ANSWERS
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
