Chemical Kinetics Test

Result

Chemical Kinetics Test - 6

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

Directions For Questions

The following question has four choices out of which ONLY ONE is correct.

...view full instructions

The experimental rate law for a reaction 2A + 2B → P is R = C_aC_b^1/2. If the concentrations of both A and B are doubled, the rate of reaction is increased by

A
1.414 times

B
5.64 times

C
2.82 times

D
4 times

Solution

This option is correct because R = [2C_a][2C_b]^1/2. Hence, this option is correct.
Question 2
1 / -0

Which of the following statements regarding the factors affecting the chemical reactions is incorrect?

A
The rate of photochemical reaction is independent of radiations.

B
A catalyst increases the rate of a chemical reaction at a particular temperature only.

C
The rate of chemical reaction is directly proportional to the concentration of the reactants.

D
The rate of chemical reaction depends on the number of collisions.

Solution

The rate of photochemical reaction increases by absorption of photons of certain radiations.
Question 3
1 / -0

Which of the following methods is used to determine the order of a reaction with respect to one reactant at a time?

A
Ostwald isolation method

B
Hit and trial method

C
Graphical method

D
Half-life method

Solution

Ostwald isolation method is used to determine the order of a reaction, with respect to one reactant at a time. The total order of the reaction can be calculated by adding all the individual orders.
Question 4
1 / -0

Directions For Questions

The following question has four choices out of which ONLY ONE is correct.

...view full instructions

On fermentation of sugar in an enzymatic solution that is initially 0.24 M, the concentration of sugar reduces to 0.06 M in 20 hours and 0.015 M in 40 hours. Which of the following statements is correct?

A
The reaction is not of first order.

B
Half-life of the reaction is 10 hours.

C
The rate constant of the reaction is 5.9 ×10^-5s^-1.

D
Half-life remains the same if the temperature increases by 10^oC.

Solution

This is false. In 20 hours, the concentration is reduced to one-fourth of the original. In next 20 hours, it is again reduced by the same factor, i.e. 1/4. So, the reaction is of first order.

Since the concentration reduces by a factor of ¼ in 20 hours, the half-life is 1/2 20 = 10 hours.
So, (2) is correct.
Since the reaction is a first order reaction,

So, K = 0.693/t_1/2 = 0.693/10 = (6.9 ×10^-4) /(3.6 ×10³ ) = 1.9 ×10^-5s^-1
So, (3) is false.

Rate constant increases with rise in temperature. Since t_1/2 is inversely proportional to the rate constant, t_1/2 decreases with rise of temperature.

So, (4) is wrong.