Consider the reaction: 2 H2O2(aq) → 2 H2O(l ) + O2( g) The graph shows the concentration of H2O2 as a function of time. Use the graph to calculate each quantity: d. If the initial volume of the H2O2 is 1.5 L, what total amount of O2 (in moles) is formed in the first 50 s of reaction?
Ch.15 - Chemical Kinetics
Chapter 15, Problem 37c
This graph shows a plot of the rate of a reaction versus the concentration of the reactant A for the reaction A → products. c. Write a rate law for the reaction including an estimate for the value of k.

1
Identify the order of the reaction by analyzing the graph. If the rate is directly proportional to the concentration of A, it is first order. If the rate is proportional to the square of the concentration of A, it is second order.
Write the general form of the rate law based on the order determined. For a first-order reaction, the rate law is: rate = k[A]. For a second-order reaction, the rate law is: rate = k[A]^2.
Estimate the value of the rate constant k by using a point from the graph. Choose a point where the concentration of A and the corresponding rate are given.
Substitute the values of the concentration of A and the rate into the rate law equation to solve for k.
Express the rate law with the estimated value of k, including the units of k based on the order of the reaction.

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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Rate Law
The rate law expresses the relationship between the rate of a chemical reaction and the concentration of its reactants. It is typically formulated as rate = k[A]^n, where k is the rate constant, [A] is the concentration of reactant A, and n is the order of the reaction with respect to A. The order can be determined experimentally and indicates how the rate is affected by changes in concentration.
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Rate Law Fundamentals
Reaction Order
The reaction order is a key concept in kinetics that describes how the rate of a reaction depends on the concentration of reactants. It can be zero, first, second, or higher, depending on how the rate changes with varying concentrations. For example, a first-order reaction means that doubling the concentration of the reactant will double the reaction rate.
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Average Bond Order
Rate Constant (k)
The rate constant, denoted as k, is a proportionality factor in the rate law that is specific to a given reaction at a particular temperature. It reflects the speed of the reaction; a larger k indicates a faster reaction. The value of k can be determined experimentally and is influenced by factors such as temperature and the presence of catalysts.
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Related Practice
Textbook Question
Textbook Question
This graph shows a plot of the rate of a reaction versus the concentration of the reactant A for the reaction A → products. a. What is the order of the reaction with respect to A?
Textbook Question
This graph shows a plot of the rate of a reaction versus the concentration of the reactant.
a. What is the order of the reaction with respect to A?
Textbook Question
This graph shows a plot of the rate of a reaction versus the concentration of the reactant.
b. Make a rough sketch of a plot of [A] versus time
Textbook Question
This graph shows a plot of the rate of a reaction versus the concentration of the reactant.
c. Write a rate law for the reaction including the value of k.