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Ch.14 - Chemical Kinetics
Chapter 14, Problem 40b

A reaction in which A, B, and C react to form products is zero order in A, one-half order in B, and second order in C. b. What is the overall order of the reaction? order in A, one-half order in B, and second order in C

Verified step by step guidance
1
Identify the order of the reaction with respect to each reactant: zero order in A, one-half order in B, and second order in C.
Recall that the overall order of a reaction is the sum of the orders with respect to each reactant.
Add the orders of each reactant: 0 (for A) + 0.5 (for B) + 2 (for C).
Calculate the sum to determine the overall order of the reaction.
The overall order of the reaction is the result of the sum from the previous step.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Reaction Order

The reaction order is a key concept in chemical kinetics that describes the relationship between the concentration of reactants and the rate of the reaction. It is determined by the sum of the powers of the concentration terms in the rate law. For example, if a reaction is first order in a reactant, doubling its concentration will double the reaction rate.
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Zero Order Reactions

A zero order reaction is one where the rate of reaction is independent of the concentration of the reactant. This means that changes in the concentration of the reactant do not affect the rate, which remains constant. Zero order reactions often occur when a catalyst is saturated or when the reaction is limited by a surface area.
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Fractional Order Reactions

Fractional order reactions, such as one-half order, indicate a non-integer relationship between the concentration of a reactant and the rate of reaction. This can occur in complex mechanisms where the reaction involves multiple steps or intermediates. Understanding fractional orders is crucial for accurately determining the overall reaction order and predicting reaction behavior.
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Related Practice
Textbook Question

A reaction in which A, B, and C react to form products is first order in A, second order in B, and zero order in C. b. What is the overall order of the reaction?

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Textbook Question

A reaction in which A, B, and C react to form products is first order in A, second order in B, and zero order in C c. By what factor does the reaction rate change if [A] is doubled (and the other reactant concentrations are held constant)? d. By what factor does the reaction rate change if [B] is doubled (and the other reactant concentrations are held constant)? e. By what factor does the reaction rate change if [C] is doubled? f. By what factor does the reaction rate change if the concentrations of all three reactants are doubled?

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Textbook Question

A reaction in which A, B, and C react to form products is zero order in A, one-half order in B, and second order in C. a. Write a rate law for the reaction.

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Textbook Question

A reaction in which A, B, and C react to form products is zero order in A, one-half order in B, and second order in C. c. By what factor does the reaction rate change if [A] is doubled (and the other reactant concentrations are held constant)? d. By what factor does the reaction rate change if [B] is doubled? e. By what factor does the reaction rate change if [C] is doubled? f. By what factor does the reaction rate change if [C] is doubled (and the other reactant concentrations are held constant)?

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Open Question
Consider the data showing the initial rate of a reaction (A → products) at several different concentrations of A. What is the order of the reaction? Write a rate law for the reaction including the value of the rate constant, k.
Open Question
Consider the tabulated data showing the initial rate of a reaction (A → products) at several different concentrations of A. What is the order of the reaction? Write a rate law for the reaction including the value of the rate constant, k.