Q. No.A first-order reaction has a specific reaction rate of
10–2 sec–1. How much time will it take for 20 g of the reactant to reduce to 5 g?
1.
138.6 sec
2.
346.5 sec
3.
693.0 sec
4.
238.6 sec
10–2 sec–1. How much time will it take for 20 g of the reactant to reduce to 5 g?
The incorrect statement among the following is:
| 1. | The value of the equilibrium constant is changed in the presence of a catalyst. |
| 2. | Enzymes catalyze mainly bio-chemical reactions. |
| 3. | Coenzymes increase the catalytic activity of the enzyme. |
| 4. | The catalyst does not initiate any reaction. |
| 1. | Internal energy | 2. | Enthalpy |
| 3. | Activation energy | 4. | Entropy |
| 1. | 269 kJ mol–1 | 2. | 34.7 kJ mol–1 |
| 3. | 15.1 kJ mol–1 | 4. | 342 kJ mol–1 |
A reaction having equal energies of activation for forward and reverse reaction has:
1. ΔG = 0
2. ΔH = 0
3. ΔH = ΔG = ΔS = 0
4. ΔS = 0
In a reaction, A + B → Product, the rate is doubled when the concentration of B is doubled, and the rate increases by a factor of 8, when the concentrations of both the reactants (A and B) are doubled. The rate law for the reaction can be written as:
1. Rate = k[A][B]2
2. Rate = k[A]2[B]2
3. Rate = k[A][B]
4. Rate = k[A]2[B]
Which of the following represents the factor by which the rate of a zero-order reaction increases when the temperature is raised from 10°C to 100°C, if the rate doubles for every 10°C rise in temperature?
1. 256 times
2. 512 times
3. 64 times
4. 128 times
If the rate constant for a first order reaction is k, the time (t) required for the completion of 99% of the reaction is given by:
1. t = 2.303/k
2. t = 0.693/k
3. t = 6.909/k
4. t = 4.606/k
The mechanism of a hypothetical reaction X2 + Y2 → 2XY is given below:
(i) X2 → X + X (Fast)
(ii) X + Y2 ⇄ XY + Y (slow)
(iii) X + Y → XY (Fast)
The overall order of the reaction will be:
1. 2
2. 0
3. 1.5
4. 1
| 1. | 3.2 × 104 s-1 | 2. | 1.6 × 106s-1 |
| 3. | 1.6 × 103 s-1 | 4. | 3.2 × 106 s-1 |
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