In the first-order reaction, half of the reaction is completed in 100 seconds. The time for 99% reaction to occur will be: |
664.64 s 646.6 s 660.9 s 654.5 s |
664.64 s |
The correct answer is option 1. 664.64 s. To determine the time for 99% of the reaction to occur in a first-order reaction, we can use the formula: \(t_{\text{99%}} = \frac{-\ln(1 - 0.99)}{k} \) Given that half of the reaction is completed in 100 seconds, we can use this information to find the rate constant (\( k \)). Since it is a first-order reaction, the half-life (\( t_{1/2} \)) is related to the rate constant by: \( t_{1/2} = \frac{0.693}{k} \) Substituting the given half-life of 100 seconds, we can solve for the rate constant \(k = \frac{0.693}{100} = 0.00693 \) Now we can substitute this value of \( k \) into the equation for \( t_{\text{99%}} \): \(t_{\text{99%}} = \frac{-\ln(1 - 0.99)}{0.00693} \) Evaluating this expression, we find: \( t_{\text{99%}} \approx 664.64 \) seconds Therefore, the correct answer is (1) 664.64 seconds. |