For an lst order reaction, k = (8.5×105)e–15000K/T. The activation energy of the reaction is:
1. 150 kJ/mol
2. 125 kJ/mol
3. 50 kJ/mol
4. 500 kJ/mol
Select the correct option based on statements below:
Assertion (A): | For elementary reactions, the law of mass action and the rate of law expression are generally the same. |
Reason (R): | The molecularity of an elementary reaction is always one. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
5 g radioactive substance is taken in 1 L flask. How much substance will be left after 100 years, if half-life of substance in 25 years?
1. 2.5 g
2. 1.5 g
3. 0.625 g
4. 0.3125 g
If a reaction A + B → C is exothermic to the extent of 30 kJ mol−1 and the forward reaction has an activation energy of 249 kJ mol−1, the activation energy for the reverse reaction in kJ mol-1 will be:
1. | 324 | 2. | 279 |
3. | 40 | 4. | 100 |
The rate constant of a reaction is
3 x 10-3 mol-2 L2s-1. Hence, the order is:
1. 1
2. Zero
3. 2
4. 3
For a zero-order reaction, the initial amount of reaction is 20 g and half-life is 30 minutes. The amount of reactant left after 60 minutes would be:
1. 5 g
2. 10 g
3. 2.5 g
4. Zero
The rate constant of the given reaction-
R(g) \(\xrightarrow[]{\Delta }\) 2P(g) is 2.48 × 10–4 s–1.
A 1 : 1 molar ratio of R to P in the reaction mixture is attained after:
1. 32 min
2. 27.3 min
3. 20 min
4. 0 min
An increase in the concentration of the reactants of a reaction leads to a change in:
1. | Heat of reaction | 2. | Threshold energy |
3. | Collision frequency | 4. | Activation energy |
When the temperature of a reaction increases from 300 K to 310 K, the rate of the reaction doubles. What is the activation energy for this reaction?
\((R=8.314 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1} \text { and } \log 2=0.301)\)
1. | \(53.6 \mathrm{~kJ} \mathrm{~mol}^{-1} \) | 2. | \(68.6 \mathrm{~kJ} \mathrm{~mol}^{-1} \) |
3. | \(59.5 \mathrm{~kJ} \mathrm{~mol}^{-1} \) | 4. | \(70.5 \mathrm{~kJ} \mathrm{~mol}^{-1}\) |
For a reaction, activation energy and the rate constant at 200 K is 1.6 . The rate constant at 400K will be [Given that gas constant, R=8.314 J ]
1. 3.2 × 104 s-1
2. 1.6 × 106s-1
3. 1.6 × 103 s-1
4. 3.2 × 106 s-1