NEET Chemistry - New - Chemical Kinetics

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Question - 1

The correct difference between first and second order reactions is that :

  • A A first-order reaction can catalyzed; a second-order reaction cannot be catalyzed.
  • B The half-life of a first-order reaction does not depend on [A]0; the half-life of a second-order reaction does depend on [A]0.
  • C The rate of a first-order reaction does not depend on reactant concentrations; the rate of a second-order reaction does depend on reactant concentrations.
  • D The rate of a first-order reaction does depend on reactant concentrations; the rate of a secondorder reaction does not depend on reactant concentrations.

Question - 2

When initial concentration of the reactant is doubled, the half-life period of a zero-order reaction :

  • A Is tripled
  • B Is doubled
  • C Is halved
  • D Remains unchanged

Question - 3

The decomposition of phosphine (PH3) on tungsten at low pressure is a first-order reaction. It is because the :

  • A rate is proportional to the surface coverage
  • B rate is inversely proportional to the surface coverage
  • C rate is independent of the surface coverage
  • D rate of decomposition is very slow.

Question - 4

The rate of first-order reaction is 0.04 mol L-1 s-1 at 10 seconds and 0.03 mol L-1 s-1 at 20 seconds after initiation of the reaction. The half-life period of the reaction is :

  • A 44.1 s
  • B 54.1 s
  • C 24.1 s
  • D 34.1 s

Question - 5

When initial concentration of a reaction is doubled in a reaction, its half-life period is not affected. The order of the reaction is :

  • A zero
  • B second
  • C first
  • D more than zero but less than first

Question - 6

The rate constant of the reaction A \(\longrightarrow \) B is 0.6 x 10-3 mole per second. If the concentration of A is 5M then concentration of B after 20 min is :

  • A 1.08 M
  • B 3.60 M
  • C 0.36 M
  • D 0.72 M

Question - 7

In a reaction, A + B ⟶ Product, rate is doubled when the concentration of B is doubled and rate increases by a factor of 8 when the concentrations of both the reactants (A and B) are doubled. Rate law for the reaction can be written as :

  • A rate = k [A][B]2
  • B rate = k [A]2 [B]2
  • C rate = k [A][B]
  • D rate = k [A]2 [B]

Question - 8

For the reaction,  \({ N }_{ 2 }{ O }_{ 5{ (g) } }\longrightarrow 2N{ O }_{ 2{ (g) } }+\frac { 1 }{ 2 } { O }_{ 2{ (g) } }\). The value of rate of disappearance of N2O5 is given as 6.25 x 10-3 mol L-1s-1. The rate of formation of NO2 and O2 is given respectively as :

  • A 6.25 x 10-3 mol L-1 s-1 and 6.25 x 10-3 mol L-1 s-1
  • B 1.25 x 10-2 mol L-1s-1 and 3.125 x 10-3 mol L-1s-1
  • C 6.25 x 10-3 mol L-1s-l and 3.125 x 10-3 mol L-1 s-1
  • D 1.25 x 10-2 mol L-1s-1 and 6.25 x 10-3 mol L-1s-1

Question - 9

During the kinetic study of the reaction, 2A + B ⟶ C + D, following results were obtained :

Run A/mol L-1 B/mol L-1 Initial rate of formation of d/mol L-1min-1
 I    0.1    0.1      6.0 x 10-3
 II    0.3    0.2    7.2 x 10-2
 III    0.3    0.4    2.88 x 10-1
 IV    0.4    0.1    2.40 x 10-2

Based on the above data which one of the followmg is correct?

  • A Rate = k [A]2[B]
  • B Rate = k [A][B]
  • C Rate = k [A]2[B]2
  • D Rate = k [A][B]2

Question - 10

In the reaction BrO-3(aq) + 5Br-(aq) + 6H+ ⟶ 3Br2 + 3H2O(l) the rate of appearance of bromine (Br2)is related to rate of disappearance of bromide ions as following:

  • A \(\frac { d[{ Br }_{ 2 }] }{ dt } =-\frac { 3 }{ 5 } \frac { d[{ Br }^{ - }] }{ dt } \)
  • B \(\frac { d[{ Br }_{ 2 }] }{ dt } =-\frac { 5 }{ 3 } \frac { d[{ Br }^{ - }] }{ dt } \)
  • C \(\frac { d[{ Br }_{ 2 }] }{ dt } =\frac { 5 }{ 3 } \frac { d[{ Br }^{ - }] }{ dt } \)
  • D \(\frac { d[{ Br }_{ 2 }] }{ dt } =\frac { 3 }{ 5 } \frac { d[{ Br }^{ - }] }{ dt } \)