A first-order reaction takes 40 min for 30 % decomposition. The t_1/2 for this reaction will be:

1.	77.7 min	2.	27.2 min
3.	55.3 min	4.	67.3 min

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:

The kinetic data for the reaction: 2A + B₂ → 2AB are as given below

The order of reaction with respect to A and B₂ is, respectively:

The rate constant, activation energy and Arrhenius factor of a reaction at 25°C are
3.0 × 10⁻⁴ s⁻¹, 104.4 kJ mol⁻¹, and 6.0 × 10¹⁴ s⁻¹, respectively.
Find the rate constant as the temperature approaches infinity.

1. 2.0 × 10¹⁸ s^-1                                                  

2. 6.0 × 10¹⁴ s^-1

3. $Infinity\; (\infty )$                                                                   

4. 3.6 × 10³⁰ s^-1

The gas phase decomposition 2N₂O₅ → 4NO₂ + O₂ follows the first order rate law, K = 7.5 × 10^-3 sec^-1. The initial pressure of N₂O₅${\mathrm{<mspace\; width="1em"></mspace>}}_{}$is 0.1 atm. The time of decomposition of N₂O₅ so that the total pressure becomes 0.15 atm will be :

If in the fermentation of sugar in an enzymatic solution that is 0.12 M, the concentration of the sugar is reduced to 0.06 M in 10 h and to 0.03 M in 20 h, the order of the reaction will be:

1. 1                                                   

2. 2

3. 3                                                   

4. 0

In a first-order reaction A $\to$ 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. $2.17$ $\times$ ${10}^{-2}$ $mi{n}^{-1}$

2. $3.46$ $\times$ ${10}^{-2}$ $mi{n}^{-1}$

3. $3.46$ $\times$ ${10}^{-3}mi{n}^{-1}$

4. $2.16$ $\times$ ${10}^{-3}$ $mi{n}^{-1}$

A catalyst lowers the activation energy of a reaction from 20 kJ mol^–1 to 10 kJ mol^-1. The temperature at which the uncatalysed reaction will have the same rate as that of the catalysed at 27 ^oC will be:
1. \(-123\ ^{\circ}C\)
2. \(-327\ ^{\circ}C\)
3. \(327\ ^{\circ}C\)
4. \(23\ ^{\circ}C\)

The rate of a reaction becomes three times when the temperature is increased from 20 °C to 50 °C.
Calculate the activation energy of the reaction.

The half-life time for the decomposition of a substance dissolved in ${\mathrm{CCl}}_4$ is 2.5 hours at \(30^{\circ} \mathrm{C}\) The amount of substance that will be left after 10 hours if the initial weight of the substance is 160 gm is: