Chemical Kinetics

The reaction of hydrogen and iodine monochloride is given as: H2(g) + 2ICl(g) 2HCl(g) + I2(g) This reaction is of first order with respect to H2(g) and ICl(g). The following mechanisms were proposed. Mechanism A: H2(g) + 2ICl(g) 2HCl(g) + I2(g) Mechanism B: H2(g) + ICl(g) HCl(g) + HI(g); slow HI(g) + ICl(g) HCl(g) + I2(g); fast Which of the above mechanism(s) can be consistent with the given information about the reaction?

1. A and B both
2. Neither A nor B
3. A only
4. B only

Consider the reaction : N2(g) + 3H2(g) 2NH3(g) The equality relationship between d[NH3]dt and - d[H2]dt is

1. d[NH3]dt = - d[H2]dt
2. d[NH3]dt = - 13 d[H2]dt
3. + d[NH3]dt = - 23 d[H2]dt
4. + d[NH3]dt = - 32 d[H2]dt

For the reaction, 2A + B 3C + D, which of the following does not express the reaction rate?

1. - d[A]2dt
2. - d[C]3dt
3. - d[B]dt
4. d[D]dt

The rate of reaction between two reactants A and B decreases by a factor of 4 if the concentration of reactant B is doubled. The order of this reaction with respect to reactant B is

1. 2
2. -2
3. 1
4. -1

For a first order reaction A B the reaction rate at reactant concentration of 0.01 M is found to be 2.0 10-5 mol L-1 s-1. The half-life period of the reaction is

1. 30 s
2. 220 s
3. 300 s
4. 347 s

The rate of a first order reaction is 1.5 10-2 mol L-1 min-1 at 0.5 M concentration of the reactant. The half-life of the reaction is

1. 0.383 min
2. 23.1 min
3. 8.73 min
4. 7.53 min

The temperature dependence of rate constant (k) of a chemical reaction is written in terms of Arrhenius equation, k = A e-E*/RT. Activation energy (E*) of the reaction can be calculated by plotting

1. k vs T
2. k vs 1 T
3. log k vs 1T
4. log k vs 1 T

If the rate of the reaction is equal to the rate constant, the order of the reaction is

1. 0
2. 1
3. 2
4. 3

The reaction A B follows first order kinetics. The time taken for 0.8 mole of A to produce 0.6 mole of B is 1 hour. What is the time taken for conversion of 0.9 mole of A to produce 0.675 mole of B?

1. 1 hour
2. 0.5 hour
3. 0.25 hour
4. 2 hours

The activation energy for a simple chemical reaction A B is Ea in forward direction. The activation energy for reverse reaction

1. is negative of Ea
2. is always less than Ea
3. can be less than or more than Ea
4. is always double of Ea