The decomposition of sucrose follows the first-order rate law. For this decomposition, t1/2 is 3.00 hours. The fraction of a sample of sucrose that remains after 8 hours would be:
1. | 0.13 | 2. | 0.42 |
3. | 0.16 | 4. | 0.25 |
The decomposition of hydrocarbons follows the equation: k = (4.5 × 1011s–1) e–28000K/T
The activation energy (Ea) for the reaction would be:
1. 232.79 kJ mol–1
2. 245.86 kJ mol–1
3. 126.12 kJ mol–1
4. 242.51 kJ mol–1
The rate constant for the first-order decomposition of H2O2 is given by the equation:
\(log \ k \ = \ 14.34 \ - \ 1.25 \ \times \ 10^{4}\frac{K}{T}\).
The value of Ea for the reaction would be:
1. 249.34 kJ mol–1
2. 242.64 J mol–1
3. –275.68 kJ mol–1
4. 239.34 kJ mol–1
The decomposition of A into the product has a value of k as 4.5 × 103 s–1 at 10°C and energy of activation of 60 kJ mol–1. The temperature at which the rate constant becomes 1.5 × 104 s–1 would be -
1. \(24 \text { K} \)
2. \(24 ^\circ \text { C} \)
3. \(31 ^\circ \text { C} \)
4. \(38 ^\circ \text { C} \)
The time required for 10% completion of a first order reaction at 298K is equal to that required for its 25% completion at 308K. If the value of A is 4 × 1010 s–1. What will be the activation energy for the reaction ?
1. 76.64 kJ mol-1
2. 72.27 kJ mol-1
3. 68.95 kJ mol-1
4. 56.24 kJ mol-1
The rate of a reaction quadruples when the temperature changes from 293 K to 313 K. The energy of activation of the reaction would be -
1. 65.93 kJ mol–1
2. 52.85 kJ mol–1
3. 55.46 kJ mol–1
4. 60.93 kJ mol–1
For a reaction A → Product, with k = 2.0 × 10–2 s–1, if the initial concentration of A is 1.0 mol L–1, the concentration of A after 100 seconds would be :
1. | 0.23 mol L–1 | 2. | 0.18 mol L–1 |
3. | 0.11 mol L–1 | 4. | 0.13 mol L–1 |
The rate constant for the decomposition of hydrocarbons is 2.418 × 10–5 s–1 at 546 K. If the energy of activation is 179.9 kJ/mol,
the value of the pre-exponential factor will be:
1.
2.
3.
4.
A first-order reaction takes 40 min for 30 % decomposition. The half life of the reaction will be:
1. | 88.8 min | 2. | 94.3 min |
3. | 67.2 min | 4. | 77.7 min |
The rate constant for a first order reaction is 60 s–1. How much time will it take to reduce the initial concentration of the reactant to its 1/16th value?