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Q1=Consider the reaction: 5 A + 3 B ?? 2 C The rate of the reaction is found to

ID: 703994 • Letter: Q

Question

Q1=Consider the reaction:

5 A + 3 B ?? 2 C

The rate of the reaction is found to be 0.0512 M/s. What is the rate of change of C? Be sure to consider whether the substance is disappearing or appearing in your answer.

Q2=For the following first order reaction, the rate of reaction is 0.77 and the [A]0 = 8.01. Calculate the rate constant.

3 A ?? 2 B

Q3=Consider the following reaction. Use the rate data to write the rate law.

2 A + B ?? 2 C

Trial

[A]0

[B]0

[C]0

Rate (M/s)

1

0.45

0.68

0.038

4.803

2

0.9

0.68

0.038

9.606

3

0.45

1.36

0.038

19.212

    ?012

    ?012

rate

= k[A]

[B]

Q4= Consider the following reaction.

2 A + B ?? 2 C

Trial

[A]0

[B]0

[C]0

Rate (M/s)

1

0.14

0.46

0.08

7.819

2

0.28

0.46

0.08

15.638

3

0.14

0.92

0.08

15.638

What is the order with respect to B? 0,1,2,3, OR 4?

Q5= Consider the following reaction. Calculate the rate of reaction for trial 4..

2 A + B ?? 2 C

Trial

[A]0

[B]0

[C]0

Rate (M/s)

1

0.5

0.73

0.075

7.55

2

1

0.73

0.075

15.1

3

0.5

1.46

0.075

30.2

4

0.5

0.8

0.075

?

Q6= For the following first order reaction, the half-life is 89.1 and the [A]0 = 1.72. Calculate the rate constant.

2 A ?? 3 B

Q7= Consider the following reaction.

aA +bB ?? cC

whose first and second half-lives are 29.6 and 14.8 minutes respectively. If the rate constant is equal to 0.2287 and [A]0 = 13.54, calculate the [A] at t = 17.38 minutes.

Q8= Consider the following reaction

2 AX + 2 I ?? 2 AI + 2 X

where the following mechanism has been proposed:

2 AX + B

??

A2B + 2 X

A2B + 2 I

??

2 AI + B

What is the catalyst in this reaction?

Options are: AX, B, X, A_2B OR I

Q9= A researcher raises the temperature from 16 to 27.5 o C and finds that the rate of the reaction doubles. What was the activation energy (in Joules) for this reaction? (R = 8.3145 J/molK)

Q10= Consider the following reaction.

2 A + B + 2 C ?? 2 D + E

The following data was collected on the reaction.

Trial

[A]0

[B]0

[C]0

Rate (M/s)

1

0.41

0.36

0.41

1.638

2

0.82

0.36

0.41

3.276

3

0.41

0.72

0.41

3.276

4

0.41

0.36

0.82

1.638

Two mechanisms are proposed:

Mechanism 1:

A + B

??

D + Y

Y + C

??

X

X + A + C

??

D + Z

Z + A

??

E

Mechanism 2:

A + C

??

D + Y

Y + B + C

??

X + D

X + A + C

??

E

Which mechanism best fits the data?     Select an answer (A) Mechanism (B) 1Mechanism 2

Which is most likely the rate-determining step?      Select an answer (a) Step 1 (b) Step 2 (c) Step 3 (d) Step 4

Q11= The reaction A ? B + C is second order with respect to A. When [A]0 = 0.296 M, the reaction is 26.2 % complete at 86.8 min. Calculate the half-life for this reaction.

Trial

[A]0

[B]0

[C]0

Rate (M/s)

1

0.45

0.68

0.038

4.803

2

0.9

0.68

0.038

9.606

3

0.45

1.36

0.038

19.212

Explanation / Answer

Ans 1

the given reaction

5 A + 3 B = 2 C

rate of the reaction = 0.0512 M/s

Rate of consumption of A, (-rA) = 0.0512 M/s

rate of change of C =?

Relation between rate of consumption of reactants and Rate of formation of products

rA/(-5) = rB/(-3) = rC/2

0.0512/5 = rC/2

rC = 0.0512*2/5 = 0.02048 M/s

The value of rC is positive so the substance is appearing.