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How much time in minutes passes between 99% to 99.9% completion of a first order reaction with half life `0.3010"min"^(-1)`?

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To solve the problem of how much time passes between 99% and 99.9% completion of a first-order reaction with a half-life of 0.3010 minutes, we can follow these steps: ### Step 1: Understand the relationship between half-life and rate constant For a first-order reaction, the relationship between the half-life (t₁/₂) and the rate constant (k) is given by the formula: \[ k = \frac{0.693}{t_{1/2}} \] Given that \( t_{1/2} = 0.3010 \) minutes, we can calculate k. ### Step 2: Calculate the rate constant (k) Using the formula: \[ k = \frac{0.693}{0.3010} \] Calculating this gives: \[ k \approx 2.303 \, \text{min}^{-1} \] ### Step 3: Set up the equations for 99% and 99.9% completion For a first-order reaction, the amount of reactant remaining can be expressed as: \[ \frac{[A]_0}{[A]} = e^{kt} \] Where: - \([A]_0\) is the initial concentration, - \([A]\) is the concentration at time \( t \), - \( k \) is the rate constant, - \( t \) is the time. 1. For 99% completion: - Remaining concentration \([A] = 1\%\) of \([A]_0\) - Therefore, \(\frac{[A]_0}{[A]} = 100\) - The equation becomes: \[ 100 = e^{kt_1} \] Taking the natural logarithm: \[ kt_1 = \ln(100) \] \[ t_1 = \frac{\ln(100)}{k} \] 2. For 99.9% completion: - Remaining concentration \([A] = 0.1\%\) of \([A]_0\) - Therefore, \(\frac{[A]_0}{[A]} = 1000\) - The equation becomes: \[ 1000 = e^{kt_2} \] Taking the natural logarithm: \[ kt_2 = \ln(1000) \] \[ t_2 = \frac{\ln(1000)}{k} \] ### Step 4: Calculate \( t_1 \) and \( t_2 \) 1. Calculate \( t_1 \): \[ t_1 = \frac{\ln(100)}{2.303} \] \[ t_1 \approx \frac{4.605}{2.303} \approx 2 \, \text{minutes} \] 2. Calculate \( t_2 \): \[ t_2 = \frac{\ln(1000)}{2.303} \] \[ t_2 \approx \frac{6.908}{2.303} \approx 3 \, \text{minutes} \] ### Step 5: Find the time difference between 99% and 99.9% completion The time difference \( \Delta t \) is: \[ \Delta t = t_2 - t_1 \] \[ \Delta t = 3 \, \text{minutes} - 2 \, \text{minutes} = 1 \, \text{minute} \] ### Final Answer The time that passes between 99% and 99.9% completion of the reaction is **1 minute**. ---

To solve the problem of how much time passes between 99% and 99.9% completion of a first-order reaction with a half-life of 0.3010 minutes, we can follow these steps: ### Step 1: Understand the relationship between half-life and rate constant For a first-order reaction, the relationship between the half-life (t₁/₂) and the rate constant (k) is given by the formula: \[ k = \frac{0.693}{t_{1/2}} \] Given that \( t_{1/2} = 0.3010 \) minutes, we can calculate k. ### Step 2: Calculate the rate constant (k) ...
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