Smartbook 14.7-14.8

A(n) ___ is a protein that acts as a biological catalyst.

enyzme

Select all that apply Which of the following statements correctly describe catalysts? Select all that apply.

-Catalysts lower the activation energy of the rate-determining step in the reaction. -Catalysts provide a different mechanism for the reaction.

Which of the following attributes are characteristic of enzymes? Select all that apply.

-High rates of activity -High specificity

Which of the following can provide experimental data that supports a proposed reaction mechanism?

-Isotope labeling experiments -Detection or characterization of a reaction intermediate

Which of the following are examples of heterogeneous catalysis? Select all that apply.

-Oxides of nitrogen are converted to O2 and N2 in a catalytic converter. -Liquid petroleum products react with hydrogen gas on the surface of platinum metal.

Which of the following are described by a reaction mechanism? Select all that apply.

-The identities of any reaction intermediates -The sequence of individual steps that make up the reaction -An explanation of the way in which the individual reactants are transformed to products

Which options correctly describe how to assess the validity of a mechanism proposed for a multistep reaction with one or more fast initial steps, given the experimentally determined rate law? Select all that apply.

-The overall rate law will reflect the concentrations of any reactants involved in all steps up to and including the rate-determining step. -Intermediate concentrations are expressed in terms of reactant concentrations using rate laws for the fast steps.

Select all the statements that correctly describe the rate-determining step in any reaction.

-The rate law for the rate-determining step is determined using experimental data obtained for the overall reaction. -The rate-determining step is an elementary step. -The rate-determining step is always the slowest step in the reaction.

Which of the following criteria must be met for a reaction mechanism to be considered valid? Select all that apply.

-The rate law for the rate-determining step must correlate with the experimentally determined rate law. -The elementary steps must add up to the overall balanced reaction.

The use of finely powdered palladium metal to catalyze the reaction shown below is an example of ______ catalysis. C6H12 (l) + H2 (g) → C6H14 (l)

heterogeneous

The addition of aqueous H2SO4 to catalyze the hydrolysis shown below would be an example of ______ catalysis. C4H8O2 (aq) + H2O (l) → C2H4O2 (aq) + C2H6O (aq)

homogeneous

The fact that a proposed reaction mechanism is consistent with the observed rate law is not sufficient to prove that the mechanism is correct. Additional experiments are typically necessary to validate a proposed mechanism. These may include attempts to detect a(n) ______; additionally, the paths of specific atoms through a reaction mechanism can be traced through the use of ______.

intermediate; isotopes

For a proposed reaction mechanism to be valid, the rate law determined from experimental data must match the rate law for the ______.

slowest reaction step

An enzyme binds to a reactant, which is called the___ , at the ___ site of the enzyme.

substrate, active

In an example of homogeneous catalysis, the reactant(s) and the catalyst are in ______ phase(s).

the same

A __ is a substance that increases the rate of a reaction without being consumed. This type of substance is often used up and regenerated during the reaction.

Catalyst

What is an elementary reaction?

Each step that makes up a reaction mechanism

Which of the following species will appear in the overall rate law for the overall reaction 2NO (g) + Br2 (g) → 2NOBr (g), given the mechanism shown?

NO, Br2

Which of the following species will be included in the overall rate law for a multistep reaction involving 2 or more initial fast steps?

Reactants involved in all steps up to and including the rate-determining step

The ___ step in any reaction sequence determines the rate law for the overall reaction. This step is called the rate-___ step.

Slowest, determining

Which statement correctly describes the active site of an enzyme?

The active site is where the enzyme-catalyzed reaction occurs.

Click and drag on elements in order Correctly order the steps required to derive the overall rate law for a multistep reaction that has one or more fast initial steps, based on a proposed mechanism.

1.)Express the equation of each fast step preceding the rate-determine step as an equilibrium process 2.)Write the rate laws for the forward and reverse processes for each fast step that precedes the rate determining step 3.)Use the rate laws derived for the fast steps to express the concentrations of any intermediates in terms of reactant concentrations 4.)Derive an overall rate law by substituting expressions for intermediate concentrations into the rate law for the rate determining step

The reaction ___ provides information about the individual steps of a reaction, and identifies any reaction ____ which are formed during one step and consumed in a subsequent step.

Mechanism, Intermediates

What is molecularity?

The number of reactant particles that react in an elementary step