Unit 7
Chemical Kinetics
11.
What
is meant by the term rate of reaction? What is its unit? [2]
22.
Define
the terms; [2]
a)An average rate of
reaction
b)Instantaneous rate of
reaction
33.
Describe
the effect of catalyst and temperature on the rate of reaction. [2]
44.
What
is an order of reaction whose rate constant has the same unit as the rate of reaction? [2]
55.
Write
the possible rate law equation for the following third-order reaction. A + B → Product. [2]
66.
Draw
a labeled energy profile diagram to show the influence of catalysts on the rate
of a chemical reaction. [2]
77.
Rate
of reaction is doubled when the concentration of A is doubled but there is no
effect in the rate with a change in concentration of B. [2]
a)Write the rate law
b)Find out the unit of
rate constant
88.
Define
zero-order reaction and find its unit rate constant. [2]
99.
Give
one example of a reaction where order and Molecularity are equal. [2]
110.
What
is rate law? [1]
111.
Define
the terms, [2]
a)Effective collision
b)Proper orientation
112. What
are activation energy and activated complex? [2]
113.
What
are the essential conditions for the effective collision of reacting species? [2]
114.
Identify
the order of the reaction if the unit of its rate constant is liter mole-1
S-1. [2]
115.
Define the order of reaction with one example. [2]
116.
What
is the zero-order reaction? Does a zero-order reaction have zero Molecularity? [2]
117.
Define
rate constant. [1]
118.
Derive
the units of rate constant for zero, first, second and third-order reactions. [2]
119.
Define
pseudo order reaction with one example. [2]
220.
What
is the half-life of the reaction? [2]
221.
Distinguished
between order and Moleculority of a reaction. [2]
222.
Write
short notes on the collision theory of reaction rate. [5]
223.
Derive
the integrated rate law equation for a first-order reaction. [5]
224.
What
are the factors affecting the rate of reaction? Explain briefly. [5]
225.
In
a reaction, H2 + I2⇋
2HI the rate of disappearance of I2 is found to be 10-6
mole/Lit. Sec. What would be the corresponding rate of appearance of HI? [2]
226.
Define
instantaneous rate of reaction. Compare the rate of reaction of all the
components of the following reaction.
2N2O5(g)→
4NO2 (g) + O2 (g)
Find the rate of each
component in mol s-1, when 2.24 liter of O2 at NTP are
produced in 30 minutes [4]
Define the average rate
of reaction. Compare the rate of reaction of all the components of the
following reactions
4NH3 (g) + 5O2 (g) →
4NO(g) + 6H2O(g)
Find the rate of each
component in mole/s, when 1.7 gram of NH3 disappears in 20 minutes.
[4]
227. The rate of reaction A + B → P is given below as a function of
different initial concentrations of A and B.
|
[A]mole /litre |
[B] mole/litre |
Rate mole L-1
S-1 |
|
0.01 |
0.01 |
0.005 |
|
0.02 |
0.01 |
0.010 |
|
0.01 |
0.02 |
0.005 |
i) Determine the
order of reaction with respect to A and B respectively
ii) What is the
overall order of the reaction?
iii) Write the rate law
equation.
iv) Calculate the
value of the rate constant.
v) What is the half-life of A? [5]
Suppose that the rate law for the reaction A →
B has been found to be of the form Rate = K[A]m, from the following
data, determine the overall order of the reaction and the order with respect to
A. [4]
|
The initial concentration of A [M] |
Initial rate
[M/sec] |
|
0.05 |
3x10-5 |
|
0.10 |
12x10-5 |
|
0.20 |
48x10-5 |
228.
Write
the possible rate law equations of the following third-order reaction.
X + Y → Product [2]
A reaction is second order with respect to the reactant. How is the rate of reaction affected if the concentration of the
reactant is (i) tripled and (ii) reduced to half? [2]
229.
For
a reaction, 2X + Y2→ X2Y, the
following data were obtained by experiment,
|
Experiment |
[X] mol/L |
[Y] mol/L |
Initial rate of
formation of [X2Y] mol/L. Sec. |
|
1 |
0.10 |
0.10 |
6.4 × 10-3 |
|
2 |
0.30 |
0.20 |
7.2 × 10-2 |
|
3 |
0.30 |
0.40 |
2.88 × 10-1 |
|
4 |
0.40 |
0.10 |
2.4 × 10-2 |
a)What is the rate law?
b)Find the order of
reaction with respect to each reactant and overall order.
c)
Find
the unit of overall order of reaction
d)What is the initial
rate of reaction when the initial concentration of X and Y is 0.5M and 1M
respectively. [5]
330.
The
following rate data were obtained at 300K for the reaction 2A + B → C + D
|
Exp. No. |
[A] mol/L |
[B] mol/L |
Rate of the
formation of the D mol/L. Min. |
|
1. |
0.1 |
0.1 |
7.5x10-3 |
|
2. |
0.3 |
0.2 |
9x10-2 |
|
3. |
0.3 |
0.4 |
3.6x10-1 |
|
4. |
0.4 |
0.1 |
3.0x10-2 |
Calculate
i) Order with respect to A and B
ii) Overall order
iii) Rate law equation
iv) Rate constant
v) Rate of formation of D when [A] = 0.8 mol/L
and [B] =0.5 mol/L. [5]
A first-order reaction is 40% complete in 50
minutes. Calculate the value of the rate constant. At what time will the
reaction be 80% complete? [4]
331.
For
a first-order reaction, it takes 4 minutes for the initial concentration of 0.8
mol/lit to become 0.2 mol/lit what time will it take to become the
concentration to 0.04 mol/lit? [4]
332.
The
rate of a first-order reaction is 1.5 ×10-2mol/L.Min at 0.5M
concentration of the reaction. What is the half of the reaction? [2]
333.
A
first-order reaction has a specific reaction rate of 10-3 sec-1.
How much time will it take for 10 grams of the reaction to reduce to 2.5 grams? [4]
334.
A
reaction that is first order with respect to reactant A has a rate constant of 6
min-1. If with start with [A] = 0.5 mol/L, when would [A] reach the
value of 0.05 mol/L. [3]
335.
The
half-life period of a first-order reaction is 600 seconds. What percent of A
remains after 30 minutes? [3]
336.
For
a first-order reaction, the rate constant is 2.2 x10-5 sec-1.
Calculate the fraction of the reactant consumed in 1 hour and 30 minutes? [4]
337.
Show
that the time required for the completion of ¾ of a first-order reaction in twice the time required for the completion of half of the reaction. [4]
338.
Predict
the order of the reaction from each of the following: [4]
a. K= 1.7x10-5 S-1
b. K= 1.3x10-3L2mol-2
S-1
c. K= 3.5x10-4mol L-1 S-1
d. K= 4.2x10-4L mol-1 S-1
The initial rate of
reaction A + B → C was measured for several
concentrations of A and B. the observations made are recorded in the following
table.
|
Exp. No. |
[A] mol/L |
[B] mol/L |
Initial rate of
formation of C mol/L. Min |
|
1. |
0.1 |
0.1 |
4.0x10-5 |
|
2. |
0.1 |
0.2 |
4x10-5 |
|
3 |
0.2 |
0.1 |
16x10-5 |
Using the data in the
above table, determine the (a) order with respect to A and B (b) rate law
(c) the magnitude of the
rate constant. [5]
339.
A
first-order reaction has a specific rate constant of 2x10-3 sec-1.
How much time it will take for 20 grams to reduce to 5 grams? [4]
440.
A
first-order reaction is 20% complete in 20 minutes. Calculate the time taken
for the reaction to go to 80% completion. [4]
441.
If
50% of the compound is decomposed in 120 minutes, how long will it take for 90%
of the compound to decompose if the reaction is first order? [4]
442.
The
three –fourth of a first-order reaction is completed in 32 minutes. What is the
half-life period of the reaction? [4]
443.
A
first-order reaction has K= 1.5x10-6 S-1 at 30 oC.
If the reaction is allowed to run for 1 day, then what percentage of the
initial concentration would have changed into the product? [4]
