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A radioactive sample contains 1.00xx10^1...

A radioactive sample contains `1.00xx10^15` atoms and has an activity of `6.00xx10^11` Bq. What is its half-life?

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To find the half-life of a radioactive sample, we can use the relationship between activity (A), the number of radioactive atoms (N), and the decay constant (λ). The formula for activity is given by: \[ A = \lambda N \] Where: - \( A \) is the activity in Becquerels (Bq), - \( \lambda \) is the decay constant (in s\(^{-1}\)), - \( N \) is the number of radioactive atoms. ### Step-by-Step Solution: 1. **Identify the given values:** - Number of atoms, \( N = 1.00 \times 10^{15} \) atoms - Activity, \( A = 6.00 \times 10^{11} \) Bq 2. **Rearranging the formula to find the decay constant (λ):** \[ \lambda = \frac{A}{N} \] 3. **Substituting the known values into the equation:** \[ \lambda = \frac{6.00 \times 10^{11} \text{ Bq}}{1.00 \times 10^{15} \text{ atoms}} = 6.00 \times 10^{-4} \text{ s}^{-1} \] 4. **Using the relationship between half-life (T₁/₂) and decay constant (λ):** The formula for half-life is: \[ T_{1/2} = \frac{\ln(2)}{\lambda} \] Where \( \ln(2) \approx 0.693 \). 5. **Substituting the decay constant into the half-life formula:** \[ T_{1/2} = \frac{0.693}{6.00 \times 10^{-4}} \text{ s} \] 6. **Calculating the half-life:** \[ T_{1/2} \approx 1155 \text{ s} \] 7. **Converting seconds into minutes:** \[ T_{1/2} \approx \frac{1155 \text{ s}}{60} \approx 19.25 \text{ minutes} \] ### Final Answer: The half-life of the radioactive sample is approximately **1155 seconds** or **19.25 minutes**. ---

To find the half-life of a radioactive sample, we can use the relationship between activity (A), the number of radioactive atoms (N), and the decay constant (λ). The formula for activity is given by: \[ A = \lambda N \] Where: - \( A \) is the activity in Becquerels (Bq), - \( \lambda \) is the decay constant (in s\(^{-1}\)), - \( N \) is the number of radioactive atoms. ...
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