Q. No.(Given: log 2=0.301)
1. 210 s
2. 21.0 s
3. 69.3 s
4. 23.1 s
1. \(5~\text{minutes}\)
2. \(10~\text{minutes}\)
3. \(2~\text{minutes}\)
4. \(4~\text{minutes}\)
[Given: log 2.5 = 0.3979]
| 1. | \(2.726 \times 10^{-5} \mathrm{~min}^{-1}\) | 2. | \(2.276 \times 10^{-5} \mathrm{~min}^{-1}\) |
| 3. | \(2.216 \times 10^{-5} \mathrm{~min}^{-1}\) | 4. | None of the above |
For a first-order reaction A \(\rightarrow\) Products, initial concentration of A is 0.1 M, which becomes 0.001 M after 5 minutes. Rate constant for the reaction in min-1 is
| 1. | 0.2303 | 2. | 1.3818 |
| 3. | 0.9212 | 4. | 0.4606 |
1. 0.16 M
2. 0.32 M
3. 0.08 M
4. 0.04 M
Which of the following is the time required to reduce the amount of a reactant from 2.0 g to 0.2 g for a first-order reaction with rate constant \(k = 4.606 \times 10^{-3} \, \text{s}^{-1}\)?
| 1. | 200 s | 2. | 500 s |
| 3. | 1000 s | 4. | 100 s |
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
A first-order reaction has a rate constant of 2.303 × 10¯3 s¯1. The time required for 40 g of this reactant to reduce to 10 g will be
[Given that ]
| 1. | 230.3 s | 2. | 301 s |
| 3. | 2000 s | 4. | 602 s |
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 |
1. 44.1 s
2. 54.1 s
3. 24.1 s
4. 34.1 s
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