22358.Which of the following statements for order of reaction is not correct?
Order can be determined experimentally
Order of a reaction is equal to the sum of the power of concentration terms in differential rate law
It is not affected with the stoichiometric coefficients of the reactants
Order cannot be fractional
22359.The activation energy of a reaction at a given temperature is found to be 2.303 RT J mol–1. The ratio of rate constant to the Arrhenius factor is
0.1
0.01
0.001
0.02
22360.The following mechanism has been proposed for the reaction of NO and Br2 to form NOBr
NO(g) + Br2(g) ⇌ NOBr2(g)
NOBr2(g) + NO(g) → 2NOBr(g)
If the second step is rate determining step, the order of the reaction with respect to NO(g) is
0
3
2
1
22361.The following data were obtained during the first order decomposition of 2A(g) → B(g) + C(s) at a constant volume and at a particular temperature.
The rate constant in min–1 is
| Sr. No. | Time | Total pressure in Pascal |
|---|---|---|
| 1. | At the end of 10 min | 300 |
| 2. | After completion | 200 |
The rate constant in min–1 is
69.3
0.0693
6.93 × 10–4
6.93
22362.Consider an endothermic reaction, X → Y with activation energies Eb and Ef respectively for the backward and forward reactions, respectively. In general,
Eb < Ef
Eb > Ef
Eb = Ef
there is no definite relation between Eb and Ef
22363.Under the same reaction conditions, initial concentration of 1.386 mol dm–3 of a substance becomes half in 40 seconds and 20 seconds through first order and zero order kinetics respectively. Ratio $\left(\dfrac{k_1}{k_0}\right)$ of the rate constants for first order (k1) and zero order (k0) of the reaction is
0.5 mol–1 dm3
1.0 mol–1 dm–3
1.5 mol dm–3
2.0 mol–1 dm–3
22364.The rate of a chemical reaction doubles for every 10°C rise of temperature. If the temperature is raised by 50°C, the rate of the reaction increases by about
64 times
10 times
24 times
32 times
22365.In the hydrolysis of an organic chloride in presence of large excess of water,
RCl + H2O → ROH + HCl
Molecularity and order of reaction both are 2
Molecularity is 2 but order of reaction is 1
Molecularity is 1 but order of reaction is 2
Moecularity is 1 and order of reaction is also 1
22366.For the reaction A + B → products, it is observed that
(i) On doubling the concentration of A only, the rate of reaction is also doubled.
(ii) On doubling the initial concentration of both A and B, there is change by a factor of 8 in the rate of reaction.
The rate of reaction is given by
(i) On doubling the concentration of A only, the rate of reaction is also doubled.
(ii) On doubling the initial concentration of both A and B, there is change by a factor of 8 in the rate of reaction.
The rate of reaction is given by
rate = k [A] [B]
rate = k [A]2 [B]
rate = k [A] [B]2
rate = k [A]2 [B]2
22367.Which of these changes with time for a first–order reaction?
A. Rate of reaction
B. Rate constant
C. Half–life
A. Rate of reaction
B. Rate constant
C. Half–life
A only
C only
A and B only
B and C only
22368.During the kinetic study of the reaction, 2A + B → C + D, following results were obtained:
Based on the above data which one of the following is correct?
| Run | [A]/mol L–1 | [B]/mol L–1 | Initial rate of formation of D/mol L–1 min–1 |
|---|---|---|---|
| I | 0.1 | 0.1 | 6.0 × 10–3 |
| II | 0.3 | 0.2 | 7.2 × 10–2 |
| III | 0.3 | 0.4 | 2.88 × 10–1 |
| IV | 0.4 | 0.1 | 2.40 × 10–2 |
Based on the above data which one of the following is correct?
rate = k[A]2 [B]2
rate = k[A] [B]2
rate = k[A]2 [B]
rate = k[A] [B]
22369.The time taken for 10% completion of a first order reaction is 20 min. Then, for 19% completion, the reaction will take
40 mins
60 mins
30 mins
50 mins
22370.For a chemical reaction A → B, the rate of the reaction is 2 × 10–3 mol dm–3 s–1 when the initial concentration is 0.05 mol dm–3. The rate of the same reaction is 1.6 × 10–2 mol dm–3 s–1 when the initial concentration is 0.1 mol dm–3. The order of the reaction is
0
3
1
2
22371.For the reaction N2O5(g) → 2NO2(g) + $\dfrac{1}{2}$O2(g) the value of rate of disappearance of N2O5 is given as 6.25 × 10–3 mol L–1 s–1. The rate of formation of NO2 and O2 is given respectively as:
6.25 × 10–3 mol L–1 s–1 and 3.125 × 10–3 mol L–1 s–1
6.25 × 10–3 mol L–1 s–1 and 6.25 × 10–3 mol L–1 s–1
6.25 × 10–3 mol L–1 s–1 and 6.25 × 10–3 mol L–1 s–1
1.25 × 10–2 mol L–1 s–1 and 3.125 × 10–3 mol L–1 s–1
22372.For the decomposition of a compound AB at 600 K, the following data were obtained
The order for the decomposition of AB is
| [AB] mol dm–3 | Rate of decomposition of AB in mol dm–3 s–1 |
|---|---|
| 0.20 | 2.75 × 10–8 |
| 0.40 | 11.0 × 10–8 |
| 0.60 | 24.75 × 10–8 |
The order for the decomposition of AB is
0
1
2
1.5
22373.For the reaction A + B → C, it is found that doubling the concentration of A increases the rate by 4 times, and doubling the concentration of B doubles the reaction rate. What is the overall order of the reaction?
4
3/2
3
1
22374.For a first order reaction A → P, the temperature (T) dependent rate constant (k) was found to follow the equation log k = –(2000) $\dfrac{1}{T}$ + 6.0. The pre–exponential factor A and the activation energy Ea, respectively, are
1.0 × 106 s–1 and 9.2 kJmol–1
6.0 s–1 and 16.6 kJmol–1
1.0 × 106 s–1 and 16.6 kJmol–1
1.0 × 106 s–1 and 38.3 kJmol–1
22375.t1/4 can be taken as the time taken for the concentration of a reactant to drop to 3/4 of its initial value. If rate constant for a first order reaction is k, then t1/4 can be written as
0.01/k
0.29/k
0.69/k
0.75/k
22376.The time required for 100% completion of a zero order reaction is
$\dfrac{a}{2k}$
ak
$\dfrac{2k}{a}$
$\dfrac{a}{k}$
22377.Consider the reaction,
Cl2 (aq) + H2S (aq) → S(s) + 2H+(aq) + 2Cl–(aq)
The rate equation for this reaction is, rate = k [Cl2] [H2S].
Which of these mechanisms is/are consistent with this rate equation?
(a) Cl2 + H2S → H+ + Cl– + Cl+ + HS– (slow)
Cl+ + HS– → H+ + Cl– + S (fast)
(b) H2S ⇌ H+ + HS– (fast equilibrium)
Cl2 + HS– → 2Cl– + H+ + S (slow)
(a) only
(b) only
Both (a) and (b)
Neither (a) nor (b)