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1. Select the factors that affect the reaction rate:

Physical state reactants

Presence of a catalyst

Reactant concentration

All of the above

The factors that affect the reaction rate include the physical state of the reactants, the presence of a catalyst, and the reactant concentration. The physical state of the reactants can affect the surface area available for the reaction to occur, with greater surface area leading to a faster reaction rate. Catalysts can increase the rate of reaction by providing an alternative pathway with lower activation energy. The reactant concentration affects the frequency of collisions between reactant particles, with higher concentration leading to more collisions and a faster reaction rate. Therefore, all of these factors play a role in determining the reaction rate.

Explanation

The factors that affect the reaction rate include the physical state of the reactants, the presence of a catalyst, and the reactant concentration. The physical state of the reactants can affect the surface area available for the reaction to occur, with greater surface area leading to a faster reaction rate. Catalysts can increase the rate of reaction by providing an alternative pathway with lower activation energy. The reactant concentration affects the frequency of collisions between reactant particles, with higher concentration leading to more collisions and a faster reaction rate. Therefore, all of these factors play a role in determining the reaction rate.

2. Rate of appearance of NO2=6molar/sec, what is the rate of disappearance of N2O5

-3

3

12

-12

The rate of appearance of NO2 is given as 6 molar/sec. Since the reaction involves the disappearance of N2O5, the rate of disappearance of N2O5 can be assumed to be equal to the rate of appearance of NO2. Therefore, the rate of disappearance of N2O5 is also 6 molar/sec.

Explanation

The rate of appearance of NO2 is given as 6 molar/sec. Since the reaction involves the disappearance of N2O5, the rate of disappearance of N2O5 can be assumed to be equal to the rate of appearance of NO2. Therefore, the rate of disappearance of N2O5 is also 6 molar/sec.

3. If k[3A]^x and the rate law is 27k[A]^x what is the order of x?

1

3

2

0

The rate law is given as 27k[A]^x, which means the rate of the reaction is directly proportional to the concentration of A raised to the power of x. Since k is raised to the power of 3A, it can be inferred that x must be equal to 3 in order for the rate law to be consistent. Therefore, the order of x is 3.

Explanation

The rate law is given as 27k[A]^x, which means the rate of the reaction is directly proportional to the concentration of A raised to the power of x. Since k is raised to the power of 3A, it can be inferred that x must be equal to 3 in order for the rate law to be consistent. Therefore, the order of x is 3.

4. The higher the activation energy is the slower the reaction gets.

True

False

The statement is true because activation energy is the minimum amount of energy required for a chemical reaction to occur. If the activation energy is high, it means that more energy is needed for the reactants to overcome the energy barrier and form products. This results in a slower reaction rate as fewer reactant molecules possess the required energy. Conversely, if the activation energy is low, more reactant molecules have enough energy to react, leading to a faster reaction rate. Therefore, the higher the activation energy, the slower the reaction gets.

Explanation

The statement is true because activation energy is the minimum amount of energy required for a chemical reaction to occur. If the activation energy is high, it means that more energy is needed for the reactants to overcome the energy barrier and form products. This results in a slower reaction rate as fewer reactant molecules possess the required energy. Conversely, if the activation energy is low, more reactant molecules have enough energy to react, leading to a faster reaction rate. Therefore, the higher the activation energy, the slower the reaction gets.

5. The rate of the appearance of NO2=6 molar/sec what is the rate of appearance of O2?

1/2

-1/2

24

-24

The rate of appearance of NO2 is given as 6 molar/sec. Since the balanced chemical equation for the reaction is not provided, we cannot determine the stoichiometry of the reaction. Therefore, we cannot directly calculate the rate of appearance of O2. Without further information, it is not possible to determine the rate of appearance of O2.

Explanation

The rate of appearance of NO2 is given as 6 molar/sec. Since the balanced chemical equation for the reaction is not provided, we cannot determine the stoichiometry of the reaction. Therefore, we cannot directly calculate the rate of appearance of O2. Without further information, it is not possible to determine the rate of appearance of O2.

6. Calculate the rate constant of this reaction:

1.2*10^4 M^-1.s^-2

1.2*10^4 M^-2.s^-1

2.4*10^4 M^-1.s^-2

2.4*10^4 M^-2.s^-1

The rate constant of a reaction represents the speed at which the reaction occurs. It is a constant that relates the concentrations of the reactants to the rate of the reaction. In this case, the correct answer is 1.2*10^4 M^-2.s^-1. This means that the rate of the reaction is proportional to the square of the concentration of the reactants. The units M^-2.s^-1 indicate that the concentration is in moles per liter and the time is in seconds.

Explanation

The rate constant of a reaction represents the speed at which the reaction occurs. It is a constant that relates the concentrations of the reactants to the rate of the reaction. In this case, the correct answer is 1.2*10^4 M^-2.s^-1. This means that the rate of the reaction is proportional to the square of the concentration of the reactants. The units M^-2.s^-1 indicate that the concentration is in moles per liter and the time is in seconds.

7. The reaction 2A=B has a rate constant of 2.8*10^-2 s^-1 at 80c, How long will it take for A to decrease from 0.88M to 0.14M. Fine the order of A

66s , 1st order

66s ,0th order

65.8s , 2nd order

100s, 1st order

The given question asks to find the order of A in the reaction 2A=B. The rate constant of the reaction is given as 2.8*10^-2 s^-1 at 80°C. To find the order of A, we need to determine the relationship between the rate of the reaction and the concentration of A. Since the reaction is first order with respect to A, it means that the rate of the reaction is directly proportional to the concentration of A. Therefore, as A decreases from 0.88M to 0.14M, it will take 66 seconds for the concentration to decrease. Hence, the answer is "66s, 1st order".

Explanation

The given question asks to find the order of A in the reaction 2A=B. The rate constant of the reaction is given as 2.8*10^-2 s^-1 at 80°C. To find the order of A, we need to determine the relationship between the rate of the reaction and the concentration of A. Since the reaction is first order with respect to A, it means that the rate of the reaction is directly proportional to the concentration of A. Therefore, as A decreases from 0.88M to 0.14M, it will take 66 seconds for the concentration to decrease. Hence, the answer is "66s, 1st order".

8. What is the relationship between the rate and each of the following depending on Arrhenius equation: 1)T 2)A 3)Ea

1)increases 2)increases 3)decrease

1)increases 2)decrease 3)decrease

1)increases 2)increases 3)increase

1)decreases 2)increases 3)decrease

According to the Arrhenius equation, the rate of a reaction is directly proportional to the temperature (T) and the value of the pre-exponential factor (A), and inversely proportional to the activation energy (Ea). Therefore, as the temperature increases, the rate of the reaction also increases. Similarly, as the value of the pre-exponential factor increases, the rate of the reaction increases. On the other hand, as the activation energy decreases, the rate of the reaction decreases.

Explanation

According to the Arrhenius equation, the rate of a reaction is directly proportional to the temperature (T) and the value of the pre-exponential factor (A), and inversely proportional to the activation energy (Ea). Therefore, as the temperature increases, the rate of the reaction also increases. Similarly, as the value of the pre-exponential factor increases, the rate of the reaction increases. On the other hand, as the activation energy decreases, the rate of the reaction decreases.

9. Rate=k[A]^x[B]^y If X=1 and Y=2 what is the overall order of the reaction?

2

3

1

Non of the above

The overall order of a reaction is determined by the sum of the exponents (x and y) in the rate equation. In this case, since X=1 and Y=2, the sum of the exponents is 1+2=3. Therefore, the overall order of the reaction is 3.

Explanation

The overall order of a reaction is determined by the sum of the exponents (x and y) in the rate equation. In this case, since X=1 and Y=2, the sum of the exponents is 1+2=3. Therefore, the overall order of the reaction is 3.

10. If you have the following data: identify the order of y?

2

1

3

Non of the above

The correct answer is 1 because it is the second number in the given data set.

Explanation

The correct answer is 1 because it is the second number in the given data set.

11. If you have the equation below determine the relationship between the disappearance ofN2O5 and the appearance of O2

-1/2(N2O5/t)=O2/t

1/2(N2O5/t)=-O2/t

(N2O5/t)=-1/2(O2/t)

(N2O5/t)=O2/t

The given equation shows that the disappearance of N2O5 is directly proportional to the appearance of O2. This means that as the amount of N2O5 decreases over time, the amount of O2 increases at the same rate. The negative sign in front of the 1/2 indicates that the two quantities have an inverse relationship, meaning that as one increases, the other decreases. Therefore, the correct answer is -1/2(N2O5/t) = O2/t.

Explanation

The given equation shows that the disappearance of N2O5 is directly proportional to the appearance of O2. This means that as the amount of N2O5 decreases over time, the amount of O2 increases at the same rate. The negative sign in front of the 1/2 indicates that the two quantities have an inverse relationship, meaning that as one increases, the other decreases. Therefore, the correct answer is -1/2(N2O5/t) = O2/t.

12. What is the rate of the reaction when [No]=0.15M and [Br2]= 0.25M hints: you need to find x and y first. k=1.2*10^4 M^-2.s^-1

67.5M.s^-1

67.5M.s

64.5M.s^-1

64.5M^-1.s

not-available-via-ai

Explanation

not-available-via-ai

13. Which of the following equations is a first order equation?

1/[A]t=kt+1/[A]0

[A]t=-kt+[A]0

[A]t=kt-[A]0

Ln[A]t=-kt+ln[A]0

The equation ln[A]t=-kt+ln[A]0 is a first order equation because it is a linear equation in the form y=mx+c, where y is ln[A]t, x is t, m is -k, and c is ln[A]0. First order equations have a linear relationship between the dependent variable (ln[A]t) and the independent variable (t), with a constant rate of change (-k).

Explanation

The equation ln[A]t=-kt+ln[A]0 is a first order equation because it is a linear equation in the form y=mx+c, where y is ln[A]t, x is t, m is -k, and c is ln[A]0. First order equations have a linear relationship between the dependent variable (ln[A]t) and the independent variable (t), with a constant rate of change (-k).