or

or

taken

why

Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.

Don't know
Know
remaining cards
Save
0:01

 Flashcards Matching Hangman Crossword Type In Quiz Test StudyStack Study Table Bug Match Hungry Bug Unscramble Chopped Targets

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

Normal Size     Small Size show me how

Chem 178 Chaper 14

Chemical Kinetics Review

14.1) The study of how fast chemical reactions occur is called what? Chemical Kinetics
14.1) What are the four important factors that affect rates of reactions? Physical state of the reactants, concentration of the reactants, temperature of the reaction, presence of absence of a catalyst
14.2) How is the speed of a reaction measured? The change that occurs per unit time
14.2) The speed of a chemical reaction is called what? Reaction rate
14.2) What are the units for average rate? M/s
14.2) The rate at any instant in time is called what? Instantaneous rate
14.2) How do you measure instantaneous rate? Find the slope of the straight line tangent to the curve at that instant
14.2) Is there a difference between instantaneous rate and average rate? Yes
14.3) An instantaneous rate taken at time 0 can be called what? Initial rate
14.3) In general, do reaction rates increase or decrease when the concentration of reactants in increased? Increase
14.3) The proportionality constant, k, is called what? Rate constant
14.3) An equation that relates the reaction rate to the concentrations of reactants is called what? Rate law
14.3) The power to which the concentration of a reactant is raised in a rate law is called what? Reaction order
14.3) How do you find the overall reaction order? Take the sum of the reaction orders in the rate law
14.3) True or False, stoichiometric coefficients in the balanced chemical equation always correspond to the reaction orders. False
14.3) What are the three most common values for reaction orders? 0,1, and 2
14.3) True or False, fractional and negative reaction orders are possible. True
14.3) If a reaction is zero order in a reactant, what effect will doubling the initial concentration of that reactant have on the rate? No effect
14.3) If a reaction is first order in a reactant, what effect will doubling the initial concentration of that reactant have on the rate? The rate increases by a factor of two
14.3) If a reaction is second order in a reactant, what effect will doubling the initial concentration of that reactant have on the rate? The rate increases by a factor of four
14.3) If a reaction is nth order in a reactant, what effect will doubling the initial concentration of that reactant have on the rate? The rate increases by a factor of 2^n
14.3) True or False, the rate constant depends on concentration. False
14.3) True or False, the rate of reaction depends on concentration. True
14.3) True or False, the rate constant is affected by temperature. True
14.3) True or False, the rate constant is affected by presence of a catalyst. True
14.4) A plot of the natural log of the concentration of A sub t, versus t, is a straight line with slope -k and intercept natural log of the concentration of A sub 0 in which overall order of reaction? First
14.4) A plot of 1 over the concentration of A sub t, versus t, is a straight line with slope k and intercept 1 over the concentration of A sub 0 in which overall order of reaction? Second
14.4) The time required for the concentration of a reactant to decrease to half of its original value is called what? Half-life
14.4) The equation half life = 0.693/k is the half life equation for which overall order of reaction? First
14.4) The equation half life = 1/(k times the concentration of A sub 0) is the half life equation for which overall order of reaction? Second
14.5) Do most reaction rates increase or decrease as temperature increases? Increase
14.5) True or False, for molecules to react they must collide. True
14.5) Is the reaction rate faster or slower with a greater number of collisions? Faster
14.5) Do reaction rates generally increase or decrease with an increase in the concentration of reactants? Increase
14.5) Should reaction rates increase or decrease with increasing temperature? Increase
14.5) When reactant molecules collide, what two things must occur to form products? The molecules must collide with proper orientation and enough energy.
14.5) The minimum energy required to initiate a chemical reaction is called what? Activation energy
14.5) The energy barrier between the starting molecule and the highest energy state found along the reaction pathway is called what? Activation energy
14.5) The species at the top of the energy barrier in a reaction pathway is called what? Transition state or activated complex
14.5) Is the reaction rate faster or slower with a lower activation energy? Faster
14.5) If a forward reaction is exothermic, is its reverse reaction exothermic or endothermic? Exothermic
14.5) How much energy do molecules need in proportion to the activation energy in order to have sufficient energy to react? Equal to or greater than
14.6) What is a reaction mechanism? The process by which a reaction occurs
14.6) Processes that occur in a single step are what kind of reactions? Elementary
14.6) What is the term for a reaction that involves just one reactant molecule? Unimolecular
14.6) Reactions that involve the collision of two molecules are what type of reactions? Bimolecular
14.6) Elementary reactions that involve the simultaneous collision of three molecules (statistically improbable) is what type of reaction? Termolecular
14.6) Which species appears in an elementary step but are not a reactant or product in the final balanced chemical equation? Intermediate
14.6) Are bimolecular processes first order, second order, or third order? Second
14.6) Is the rate-determining step in a multistep reaction the slowest step or the fastest step? Slowest step
14.6) Which step in a multistep reaction governs the overall rate law for the overall reaction? Rate-determining step
14.6) Can intermediates found in a multistep mechanism be used in the overall rate law? No
14.7) What is the name of the substance that changes the rate of a chemical reaction without itself undergoing a permanent chemical change? Catalyst
14.7) Does a homogeneous or a heterogeneous catalyst exist in the same phase as the reacting molecules? Homogeneous
14.7) How do catalysts increase reaction rates? Lowering the overall activation energy
14.7) Is the process of binding reactant molecules a surface called absorption or adsorption? Adsorption
14.7) Is the uptake of molecules into the interior of another substance called absorption or adsorption? Absorption
14.7) What is the term for a biological catalyst? Enzyme
Created by: kbruning