Reaction Rate and Rate Laws - MCAT Chemical and Physical Foundations of Biological Systems
Card 1 of 98
The rate for a reaction is given by the equation 
. What is the overall order of the reaction?
The rate for a reaction is given by the equation
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To find the overall order of a reaction, look at the exponents for the reaction rate law. Since A has an exponent of two and B has an exponent of one, the overall reaction has an order of three.
To find the overall order of a reaction, look at the exponents for the reaction rate law. Since A has an exponent of two and B has an exponent of one, the overall reaction has an order of three.
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A kinetics experiment is constructed, and the following rates of product formation are observed after adding various substrates. The results are recorded below. What is the equation for the rate law?
A B C Initial Rate (M/s) 0.1M 0.2M 0.2M 1.5 0.2M 0.2M 0.2M 3 0.2M 0.2M 0.4M 3 0.2M 0.4M 0.2M 12
A kinetics experiment is constructed, and the following rates of product formation are observed after adding various substrates. The results are recorded below. What is the equation for the rate law?
| A | B | C | Initial Rate (M/s) |
|---|---|---|---|
| 0.1M | 0.2M | 0.2M | 1.5 |
| 0.2M | 0.2M | 0.2M | 3 |
| 0.2M | 0.2M | 0.4M | 3 |
| 0.2M | 0.4M | 0.2M | 12 |
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We can look at the differences between trial 1 and trial 2 to see that the reaction is first order with respect to \[A\], since the rate doubles when the reactant concentration doubles. Reactants are considered first order when this 1:1 relationship between concentration and rate is observed.
We can look at trials 2 and 3 to see that \[C\] has no effect on the reaction, making it a zeroth order reactant and simply equal to 1 in the rate law.
Trials 3 and 4 show that when \[B\] doubles, the rate quadruples. This means it is second order with respect to \[B\], increasing the rate by the square of the increase in concentration. Since we already know that reactant C does not affect the rate, it is irrelevant that its concentration is halved.
This gives us Rate = k\[A\]\[B\]2.
We can look at the differences between trial 1 and trial 2 to see that the reaction is first order with respect to \[A\], since the rate doubles when the reactant concentration doubles. Reactants are considered first order when this 1:1 relationship between concentration and rate is observed.
We can look at trials 2 and 3 to see that \[C\] has no effect on the reaction, making it a zeroth order reactant and simply equal to 1 in the rate law.
Trials 3 and 4 show that when \[B\] doubles, the rate quadruples. This means it is second order with respect to \[B\], increasing the rate by the square of the increase in concentration. Since we already know that reactant C does not affect the rate, it is irrelevant that its concentration is halved.
This gives us Rate = k\[A\]\[B\]2.
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Which of the following is a second-order rate law?
Which of the following is a second-order rate law?
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The order of a reaction or rate law is given by the sum of the exponents in the rate expression. Rate = k\[A\]1\[B\]1 is the only second-order rate law. This is the case since the reaction order is determined by the number of reactants involved. Rate = k\[A\]1\[B\]2 is not second-order; since it has one A reactant and two B reactants, this is a third-order reaction.
The order of a reaction or rate law is given by the sum of the exponents in the rate expression. Rate = k\[A\]1\[B\]1 is the only second-order rate law. This is the case since the reaction order is determined by the number of reactants involved. Rate = k\[A\]1\[B\]2 is not second-order; since it has one A reactant and two B reactants, this is a third-order reaction.
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If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
Trial PXY(torr) PZ(torr) Rate (torr/s) 1 100 200 0.16 2 200 200 0.32 3 200 100 0.04 4 200 150 0.14
What is the rate law for this reaction?
If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
| Trial | PXY(torr) | PZ(torr) | Rate (torr/s) |
|---|---|---|---|
| 1 | 100 | 200 | 0.16 |
| 2 | 200 | 200 | 0.32 |
| 3 | 200 | 100 | 0.04 |
| 4 | 200 | 150 | 0.14 |
What is the rate law for this reaction?
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Comparing trials 2 and 3, we see that when PXY is constant and PZ doubles, the rate increases by a factor of 8, or 23. Rate is therefore proportional to \[Z\]3.
Comparing trials 1 and 2, we see that when PZ is held constant and PXY doubles, the rate doubles. Rate is therefore proportional to \[XY\].
Remember that in these problems, you are looking for the value of n in the function 
. When doubling the concentration does not affect the reaction rate, n = 0. When doubling the concentration doubles the reaction rate, n = 1. When doubling the concentration quadruples the reaction rate, n = 2.
Comparing trials 2 and 3, we see that when PXY is constant and PZ doubles, the rate increases by a factor of 8, or 23. Rate is therefore proportional to \[Z\]3.
Comparing trials 1 and 2, we see that when PZ is held constant and PXY doubles, the rate doubles. Rate is therefore proportional to \[XY\].
Remember that in these problems, you are looking for the value of n in the function
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If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
Trial PXY(torr) PZ(torr) Rate (torr/s) 1 100 200 0.16 2 200 200 0.32 3 200 100 0.04 4 200 150 0.14
What is the value of the rate constant, k, for this reaction?
If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
| Trial | PXY(torr) | PZ(torr) | Rate (torr/s) |
|---|---|---|---|
| 1 | 100 | 200 | 0.16 |
| 2 | 200 | 200 | 0.32 |
| 3 | 200 | 100 | 0.04 |
| 4 | 200 | 150 | 0.14 |
What is the value of the rate constant, k, for this reaction?
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The rate law can be determined by comparing changes in reactant concentration to changes in rate. In this reaction, doubling XY doubles the reaction rate; the reaction is first-order for XY. Doubling Z increases the rate by a factor of eight, so the reaction is third-order for Z (23 = 8).
Knowing that Rate = k\[XY\] \[Z\]3, we can solve for k by using data from one of the trials. Plugging in data from trial 1, we can calculate the value of k.
0.16 = k\[100\]\[200\]3
k = 2 * 10-10
The rate law can be determined by comparing changes in reactant concentration to changes in rate. In this reaction, doubling XY doubles the reaction rate; the reaction is first-order for XY. Doubling Z increases the rate by a factor of eight, so the reaction is third-order for Z (23 = 8).
Knowing that Rate = k\[XY\] \[Z\]3, we can solve for k by using data from one of the trials. Plugging in data from trial 1, we can calculate the value of k.
0.16 = k\[100\]\[200\]3
k = 2 * 10-10
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A scientist is studying a reaction, and places the reactants in a beaker at room temperature. The reaction progresses, and she analyzes the products via NMR. Based on the NMR readout, she determines the reaction proceeds as follows:
In an attempt to better understand the reaction process, she varies the concentrations of the reactants and studies how the rate of the reaction changes. The table below shows the reaction concentrations as she makes modifications in three experimental trials.
Which of the following most closely approximates the rate law for this reaction?
A scientist is studying a reaction, and places the reactants in a beaker at room temperature. The reaction progresses, and she analyzes the products via NMR. Based on the NMR readout, she determines the reaction proceeds as follows:
In an attempt to better understand the reaction process, she varies the concentrations of the reactants and studies how the rate of the reaction changes. The table below shows the reaction concentrations as she makes modifications in three experimental trials.
Which of the following most closely approximates the rate law for this reaction?
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The reaction table in the passage indicates that the reaction rate varies in a 1-to-1 fashion as you vary the each reactant, while holding the other constant.
The rate law is written as 
.
Compare trials 1 and 2 to see that doubling the ammonium concentration doubles the rate. The reaction is first order for ammonium: 
.
Compare trials 2 and 3 to see that tripling nitrate concentration triples the rate. The reaction is first order for nitrate: 
.
The final rate law is 
.
The reaction table in the passage indicates that the reaction rate varies in a 1-to-1 fashion as you vary the each reactant, while holding the other constant.
The rate law is written as
Compare trials 1 and 2 to see that doubling the ammonium concentration doubles the rate. The reaction is first order for ammonium:
Compare trials 2 and 3 to see that tripling nitrate concentration triples the rate. The reaction is first order for nitrate:
The final rate law is
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Consider the reaction 
.
A set of trials is set up in order to see how manipulating the starting concentrations of reactants can affect the initial rate of the reaction. The experiments are outlined in the table below.
Trial Initial \[A\] Initial \[B\] Initial \[C\] Initial reaction rate (M/s) 1 0.3 0.4 0.2 0.04 2 0.3 0.4 0.6 0.12 3 0.3 0.8 0.6 0.48 4 0.6 0.4 0.2 0.04
Based on the above information, determine the rate law for the reaction.
Consider the reaction
A set of trials is set up in order to see how manipulating the starting concentrations of reactants can affect the initial rate of the reaction. The experiments are outlined in the table below.
| Trial | Initial \[A\] | Initial \[B\] | Initial \[C\] | Initial reaction rate (M/s) |
|---|---|---|---|---|
| 1 | 0.3 | 0.4 | 0.2 | 0.04 |
| 2 | 0.3 | 0.4 | 0.6 | 0.12 |
| 3 | 0.3 | 0.8 | 0.6 | 0.48 |
| 4 | 0.6 | 0.4 | 0.2 | 0.04 |
Based on the above information, determine the rate law for the reaction.
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The coefficients in front of the reactants simply show the balanced equation, and do NOT give any information on the order of the reactants. The order of the reactants must be determined experimentally by comparing how reaction rates change when the reactant's concentration is altered.
Only the reactant in question must have an altered concentration between two trials; all others must be kept constant. When a reaction rate is doubled and the initial reaction rate is quadrupled, we determine that the reaction is second order with respect to the reactant. If the concentration of a reactant is altered but the reaction rate is unaffected, the order of the reactant is zero. Finally, if the reaction rate and reactant are multiplied by the same factor between two trials, the reactant is first order.
In the table, we can compare trial 1 and 4 to see the effect of doubling A, with constant B and C. This does not affect the rate, to A must be zeroth order. Comparing trials 2 and 3 shows that doubling B, with A and C held constant, will quadruple the rate. The reaction must be second order for B. Finally, comparing trials 1 and 2 shows us that tripling C, with A and B held constant, will triple the reaction rate. The reaction must be first order for C. This yields the rate law 
.
If the concentration of a reactant is doubled, 
. The relationship between this change and the change in rate is, therefore, 
, where n is the order of the reaction with respect to X. This can be reduced to 
, allowing us to find the reaction order from the experimental rate.
The coefficients in front of the reactants simply show the balanced equation, and do NOT give any information on the order of the reactants. The order of the reactants must be determined experimentally by comparing how reaction rates change when the reactant's concentration is altered.
Only the reactant in question must have an altered concentration between two trials; all others must be kept constant. When a reaction rate is doubled and the initial reaction rate is quadrupled, we determine that the reaction is second order with respect to the reactant. If the concentration of a reactant is altered but the reaction rate is unaffected, the order of the reactant is zero. Finally, if the reaction rate and reactant are multiplied by the same factor between two trials, the reactant is first order.
In the table, we can compare trial 1 and 4 to see the effect of doubling A, with constant B and C. This does not affect the rate, to A must be zeroth order. Comparing trials 2 and 3 shows that doubling B, with A and C held constant, will quadruple the rate. The reaction must be second order for B. Finally, comparing trials 1 and 2 shows us that tripling C, with A and B held constant, will triple the reaction rate. The reaction must be first order for C. This yields the rate law
If the concentration of a reactant is doubled,
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What is the order for a reaction with the rate law given below?
What is the order for a reaction with the rate law given below?
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The reaction order is equal to the sum of the exponents of the concentration variables in the rate law.
Because reactant B has an exponent of two and reactant C has an exponent of one, the total sum is three, and the reaction is therefore third order.
The reaction order is equal to the sum of the exponents of the concentration variables in the rate law.
Because reactant B has an exponent of two and reactant C has an exponent of one, the total sum is three, and the reaction is therefore third order.
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A student is studying the kinetics of the following reaction.
In trying to determine the rate law, he collects the following set of data.
Based on these data, what is the rate law for this reaction?
A student is studying the kinetics of the following reaction.
In trying to determine the rate law, he collects the following set of data.
Based on these data, what is the rate law for this reaction?
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The rate law will have the general formula 
. The exponents, 
and 
, DO NOT necessarily correlate with the reaction stoichiometry. They must be determined from the experimental data.
To determine 
, compare trials 1 and 3, where 
is held constant.
Since 
is constant and 
is the same for both experiments, by plugging in the values for rate and 
for trials 1 and 3, we get this equation.
.
This reduces to 
, which means 
.
To find 
, compare trials 1 and 2, where 
is held constant. Following the same type of calculation as shown above would give 
.
The rate law is 
.
The rate law will have the general formula
To determine
Since
This reduces to
To find
The rate law is
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A student is studying the kinetics of the following reaction.
In trying to determine the rate law, he collects the following set of data.
What is the value of 
if the rate law is 
?
A student is studying the kinetics of the following reaction.
In trying to determine the rate law, he collects the following set of data.
What is the value of
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To determine 
, the data from any of the three trials could be used. Using trial 1 and the rate law, we can solve for 
.
Note that the units have to be adjusted, based on the order of 
and 
.
To determine
Note that the units have to be adjusted, based on the order of
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Initial Reaction Rate 
**
**M **
M ****
**M 2000 1.0 1.0 1.0 2000 1.0 1.0 2.0 4000 2.0 1.0 1.0 16000 2.0 2.0 1.0
Using data in the table above to determine the rate law for the reaction.
| Initial Reaction Rate | ****M | ** M | ******M |
|---|---|---|---|
| 2000 | 1.0 | 1.0 | 1.0 |
| 2000 | 1.0 | 1.0 | 2.0 |
| 4000 | 2.0 | 1.0 | 1.0 |
| 16000 | 2.0 | 2.0 | 1.0 |
Using data in the table above to determine the rate law for the reaction.
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Let's look at each of the three reactants individually.
Compare trials 1 and 3. Doubling 
without changing the other reactants doubles the rate from 
to 
; therefore 
has a superscript of 1.
Compare trials 3 and 4. Doubling 
without changing the other reactants results in a rate that is four times faster, increasing from 
to 
. The rate increases with the square of concentration of 
, 
Compare trials 1 and 2. Doubling 
without changing the other reactants has no effect on the rate, which remains at 
, so 
is not part of the final rate equation.
The final rate law will be 
.
Let's look at each of the three reactants individually.
Compare trials 1 and 3. Doubling
Compare trials 3 and 4. Doubling
Compare trials 1 and 2. Doubling
The final rate law will be
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A scientist is studying a reaction, and places the reactants in a beaker at room temperature. The reaction progresses, and she analyzes the products via NMR. Based on the NMR readout, she determines the reaction proceeds as follows:
In an attempt to better understand the reaction process, she varies the concentrations of the reactants and studies how the rate of the reaction changes. The table below shows the reaction concentrations as she makes modifications in three experimental trials.
What is the overall order for this reaction as written?
A scientist is studying a reaction, and places the reactants in a beaker at room temperature. The reaction progresses, and she analyzes the products via NMR. Based on the NMR readout, she determines the reaction proceeds as follows:
In an attempt to better understand the reaction process, she varies the concentrations of the reactants and studies how the rate of the reaction changes. The table below shows the reaction concentrations as she makes modifications in three experimental trials.
What is the overall order for this reaction as written?
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The rate law is written as 
.
Compare trials 1 and 2 to see that doubling the ammonium concentration doubles the rate. The reaction is first order for ammonium: 
.
Compare tirals 2 and 3 to see that tripling nitrate concentration triples the rate. The reaction is first order for nitrate: 
.
The final rate law is 
.
The sum of the orders for each reactant gives you the overall order of the reaction. In this case, the reaction is first order with regard to each reactant, and is thus second order overall.
The rate law is written as
Compare trials 1 and 2 to see that doubling the ammonium concentration doubles the rate. The reaction is first order for ammonium:
Compare tirals 2 and 3 to see that tripling nitrate concentration triples the rate. The reaction is first order for nitrate:
The final rate law is
The sum of the orders for each reactant gives you the overall order of the reaction. In this case, the reaction is first order with regard to each reactant, and is thus second order overall.
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A first-order reaction has a rate constant:
How long does it take for the concentration of the reactant to reach one-fourth of its original amount?
A first-order reaction has a rate constant:
How long does it take for the concentration of the reactant to reach one-fourth of its original amount?
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For a first order reaction, use the equation:
In this formula, 
is the concentration at a given time, 
is the initial concentration, 
is the rate constant, and 
is the time elapsed.
If we assume the initial concentration to be 
, then we can use 
as the final concentration. Using these values and the given rate constant, we can calculate the time.
For a first order reaction, use the equation:
In this formula,
If we assume the initial concentration to be
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Which of the following parameters can affect the rate of the given reaction?
Which of the following parameters can affect the rate of the given reaction?
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The rate law for the given reaction will be given by the formula:
The variables 
and 
need to be determined experimentally, and the value 
will be given by another formula.
The coefficient is a constant, and the variables in the exponent are the activation energy and temperature.
Adding an enzyme will lower the activation energy, affecting the rate constant. Changing the temperature will also affect the rate constant. Adjusting the ratio of reactants to products will alter the concentrations of the reactants. As the reaction runs, the rate declines as the reactants are consumed until it reaches equilibrium. Changing the reactant concentrations will change the reaction rate with respect to this equilibrium. Running the reaction in reverse will result in a completely different rate law since the reactants will be altered.
The rate law for the given reaction will be given by the formula:
The variables
The coefficient is a constant, and the variables in the exponent are the activation energy and temperature.
Adding an enzyme will lower the activation energy, affecting the rate constant. Changing the temperature will also affect the rate constant. Adjusting the ratio of reactants to products will alter the concentrations of the reactants. As the reaction runs, the rate declines as the reactants are consumed until it reaches equilibrium. Changing the reactant concentrations will change the reaction rate with respect to this equilibrium. Running the reaction in reverse will result in a completely different rate law since the reactants will be altered.
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What is the order for a reaction with the rate law given below?
What is the order for a reaction with the rate law given below?
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The reaction order is equal to the sum of the exponents of the concentration variables in the rate law.
Because reactant B has an exponent of two and reactant C has an exponent of one, the total sum is three, and the reaction is therefore third order.
The reaction order is equal to the sum of the exponents of the concentration variables in the rate law.
Because reactant B has an exponent of two and reactant C has an exponent of one, the total sum is three, and the reaction is therefore third order.
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The rate for a reaction is given by the equation . What is the overall order of the reaction?
The rate for a reaction is given by the equation
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To find the overall order of a reaction, look at the exponents for the reaction rate law. Since A has an exponent of two and B has an exponent of one, the overall reaction has an order of three.
To find the overall order of a reaction, look at the exponents for the reaction rate law. Since A has an exponent of two and B has an exponent of one, the overall reaction has an order of three.
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A kinetics experiment is constructed, and the following rates of product formation are observed after adding various substrates. The results are recorded below. What is the equation for the rate law?
A B C Initial Rate (M/s) 0.1M 0.2M 0.2M 1.5 0.2M 0.2M 0.2M 3 0.2M 0.2M 0.4M 3 0.2M 0.4M 0.2M 12
A kinetics experiment is constructed, and the following rates of product formation are observed after adding various substrates. The results are recorded below. What is the equation for the rate law?
| A | B | C | Initial Rate (M/s) |
|---|---|---|---|
| 0.1M | 0.2M | 0.2M | 1.5 |
| 0.2M | 0.2M | 0.2M | 3 |
| 0.2M | 0.2M | 0.4M | 3 |
| 0.2M | 0.4M | 0.2M | 12 |
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We can look at the differences between trial 1 and trial 2 to see that the reaction is first order with respect to \[A\], since the rate doubles when the reactant concentration doubles. Reactants are considered first order when this 1:1 relationship between concentration and rate is observed.
We can look at trials 2 and 3 to see that \[C\] has no effect on the reaction, making it a zeroth order reactant and simply equal to 1 in the rate law.
Trials 3 and 4 show that when \[B\] doubles, the rate quadruples. This means it is second order with respect to \[B\], increasing the rate by the square of the increase in concentration. Since we already know that reactant C does not affect the rate, it is irrelevant that its concentration is halved.
This gives us Rate = k\[A\]\[B\]2.
We can look at the differences between trial 1 and trial 2 to see that the reaction is first order with respect to \[A\], since the rate doubles when the reactant concentration doubles. Reactants are considered first order when this 1:1 relationship between concentration and rate is observed.
We can look at trials 2 and 3 to see that \[C\] has no effect on the reaction, making it a zeroth order reactant and simply equal to 1 in the rate law.
Trials 3 and 4 show that when \[B\] doubles, the rate quadruples. This means it is second order with respect to \[B\], increasing the rate by the square of the increase in concentration. Since we already know that reactant C does not affect the rate, it is irrelevant that its concentration is halved.
This gives us Rate = k\[A\]\[B\]2.
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Which of the following is a second-order rate law?
Which of the following is a second-order rate law?
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The order of a reaction or rate law is given by the sum of the exponents in the rate expression. Rate = k\[A\]1\[B\]1 is the only second-order rate law. This is the case since the reaction order is determined by the number of reactants involved. Rate = k\[A\]1\[B\]2 is not second-order; since it has one A reactant and two B reactants, this is a third-order reaction.
The order of a reaction or rate law is given by the sum of the exponents in the rate expression. Rate = k\[A\]1\[B\]1 is the only second-order rate law. This is the case since the reaction order is determined by the number of reactants involved. Rate = k\[A\]1\[B\]2 is not second-order; since it has one A reactant and two B reactants, this is a third-order reaction.
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If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
Trial PXY(torr) PZ(torr) Rate (torr/s) 1 100 200 0.16 2 200 200 0.32 3 200 100 0.04 4 200 150 0.14
What is the rate law for this reaction?
If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
| Trial | PXY(torr) | PZ(torr) | Rate (torr/s) |
|---|---|---|---|
| 1 | 100 | 200 | 0.16 |
| 2 | 200 | 200 | 0.32 |
| 3 | 200 | 100 | 0.04 |
| 4 | 200 | 150 | 0.14 |
What is the rate law for this reaction?
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Comparing trials 2 and 3, we see that when PXY is constant and PZ doubles, the rate increases by a factor of 8, or 23. Rate is therefore proportional to \[Z\]3.
Comparing trials 1 and 2, we see that when PZ is held constant and PXY doubles, the rate doubles. Rate is therefore proportional to \[XY\].
Remember that in these problems, you are looking for the value of n in the function . When doubling the concentration does not affect the reaction rate, n = 0. When doubling the concentration doubles the reaction rate, n = 1. When doubling the concentration quadruples the reaction rate, n = 2.
Comparing trials 2 and 3, we see that when PXY is constant and PZ doubles, the rate increases by a factor of 8, or 23. Rate is therefore proportional to \[Z\]3.
Comparing trials 1 and 2, we see that when PZ is held constant and PXY doubles, the rate doubles. Rate is therefore proportional to \[XY\].
Remember that in these problems, you are looking for the value of n in the function
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If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
Trial PXY(torr) PZ(torr) Rate (torr/s) 1 100 200 0.16 2 200 200 0.32 3 200 100 0.04 4 200 150 0.14
What is the value of the rate constant, k, for this reaction?
If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
| Trial | PXY(torr) | PZ(torr) | Rate (torr/s) |
|---|---|---|---|
| 1 | 100 | 200 | 0.16 |
| 2 | 200 | 200 | 0.32 |
| 3 | 200 | 100 | 0.04 |
| 4 | 200 | 150 | 0.14 |
What is the value of the rate constant, k, for this reaction?
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The rate law can be determined by comparing changes in reactant concentration to changes in rate. In this reaction, doubling XY doubles the reaction rate; the reaction is first-order for XY. Doubling Z increases the rate by a factor of eight, so the reaction is third-order for Z (23 = 8).
Knowing that Rate = k\[XY\] \[Z\]3, we can solve for k by using data from one of the trials. Plugging in data from trial 1, we can calculate the value of k.
0.16 = k\[100\]\[200\]3
k = 2 * 10-10
The rate law can be determined by comparing changes in reactant concentration to changes in rate. In this reaction, doubling XY doubles the reaction rate; the reaction is first-order for XY. Doubling Z increases the rate by a factor of eight, so the reaction is third-order for Z (23 = 8).
Knowing that Rate = k\[XY\] \[Z\]3, we can solve for k by using data from one of the trials. Plugging in data from trial 1, we can calculate the value of k.
0.16 = k\[100\]\[200\]3
k = 2 * 10-10
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