Half-life is independent of the concentration of a reactant. After 10 minutes, the volume of N2 gas is 10 L and after complete reaction, it is 50 L. Hence, the rate constant is:
1. log 5 min-1
2. log 1.25 min-1
3. log 2 min-1
4. log 4 min-1
A gaseous reaction A2(g) → B(g) + (g) shows increase in pressure from 100 mm to 120 mm in 5 minutes. The rate of disappearance of A2 will be :
1. | 4 mm min-1 | 2. | 8 mm min-1 |
3. | 16 mm min-1 | 4. | 2 mm min-1 |
During the formation of ammonia by Haber's process N2 + 3H2 → 2NH3, the rate of appearance of NH3 was measured as 2.5 x 10-4 mol L-1 s-1. The rate of disappearance of H2 will be:
1. 2.5 x 10-4 mol L-1 s-1
2. 1.25 x 10-4 mol L-1 s-1
3. 3.75 x 10-4 mol L-1 s-1
4. 15.00 x 10-4 mol L-1 s-1
The correct expression for the 3/4th life of a first-order reaction is:
From the plot of log k vs 1/T, following parameter can be calculated:
1. Activation energy.
2. Rate constant of reaction .
3. Order of reaction.
4. Activation energy as well as the frequency factor.
The rate constant for a chemical reaction that takes place at 500 K is expressed as K = A e-1000. The activation energy of the reaction will be:
1. 100 cal/mol
2. 1000 kcal/mol
3. 104 kcal/mol
4. 106 kcal/mol
In the following reaction: xA → yB
where the -ve sign indicates the rate of disappearance of the reactant. Then, x : y equals:
1. | 1:2 | 2. | 2:1 |
3. | 3:1 | 4. | 3:10 |
If the rate of reaction doubles when the temperature is raised from 20 °C to 35 °C, then the activation energy for the reaction will be :
(R = 8.314 J mol-1 K-1)
1. 342 kJ mol-1
2. 269 kJ mol-1
3. 34.7 kJ mol-1
4. 15.1 kJ mol-1
For the reaction,
N2O5(g) → 2NO2(g) + \(\frac{1}{2}\)O2(g)
the value of the rate of disappearance of is given as . The rate of formation of is given respectively as:
1. 6.25 x 10-3 mol L-1s-1 and 6.25 x 10-3 mol L-1s-1
2. 1.25 x 10-2 mol L-1s-1 and 3.125 x 10-3 mol L-1s-1
3. 6.25 x 10-3 mol L-1s-1 and 3.125 x 10-3 mol L-1s-1
4. 1.25 x 10-2 mol L-1s-1 and 6.25 x 10-3 mol L-1s-1
A first-order reaction is 15 % completed in 20 minutes. The amount of time required to complete 60 % of the reaction is:
1. | 112.8 min | 2. | 120.7 min |
3. | 100.4 min | 4. | 140.7 min |