A first-order reaction was started with a decimolar solution of the reactant. After 8 minutes and 20 seconds, its concentration was found to be M/100. The rate constant of the reaction will be:
1.
2.
3.
4.
At 400 K, the energy of activation of a reaction is decreased by 0.8 kcal in the presence of a catalyst. As a result, the rate will be:
1. | Increased by 2.71 times. | 2. | Increased by 1.18 times. |
3. | Decreased by 2.72 times. | 4. | Increased by 6.26 times. |
Given the following reaction:
N2O5 as N2O5 ⇌ 2NO2 + (1/2)O2
The values of rate constants for the above reaction are 3.45 × 10-5 and 6.9 × 10-3 at 27 oC and 67 oC respectively. The activation energy for the above reaction is :
1.
2.
3.
4.
In a first-order reaction A products, the concentration of the reactant decreases to 6.25 % of its initial value in 80 minutes. The value of the rate constant, if the initial concentration is 0.2 mole/litre, will be:
1.
2.
3.
4.
The rate constant, the activation energy, and the Arrhenius parameter of a chemical reaction at 25°C are 3.0×10-4 s-1, 104.4 kJ mol-1 and 6.0×1014s-1 respectively.
The value of the rate constant as T → ∞
will be:
1. 2.0 × 1018 s-1
2. 6.0 × 1014 s-1
3.
4. 3.6 × 1030 s-1
The kinetic data for the reaction: 2A + B2 → 2AB are as given below
[A]/mol L-1 | [B2]/mol L-1 | Rate/mol L-1s-1 |
0.5 | 1.0 | 2.5 × 10-3 |
1.0 | 1.0 | 5.0 × 10-3 |
0.5 | 2.0 | 1 × 10-2 |
The order of reaction with respect to A and B2 is, respectively:
1. | 1 and 2 | 2. | 2 and 1 |
3. | 1 and 1 | 4. | 2 and 2 |
The half-life period for a first-order reaction is 20 minutes. The time required to change the concentration of the reactants from 0.08 M to 0.01 M will be:
1. | 20 minutes | 2. | 60 minutes |
3. | 40 minutes | 4. | 50 minutes |
If a reaction A + B C is exothermic to the extent of 30 kJ/mol and the forward reaction has an activation energy of 70 kJ/mol, the activation energy for the reverse reaction will be:
1. 30 kJ/mol
2. 40kJ/mol
3. 70 kJ/mol
4. 100 kJ/mol
If ‘a’ is the initial concentration of a substance which reacts according to zero-order kinetics and k is the rate constant, the time for the reaction to go to completion will be:
1. | a/k | 2. | 2/ka |
3. | k/a | 4. | Infinite |
The graph that represents a first-order reaction is:
1. | 2. | ||
3. | 4. |