1. **State the problem:** We have two radioactive samples with given amounts over time. Sample 1 starts at 800 mg and decreases to 400 mg after 1 month. Sample 2 starts at 1000 mg and decreases to 800 mg after 1 month. We need to determine if Sample 2 decreases more rapidly than Sample 1.
2. **Formula and concept:** Radioactive decay is modeled by exponential decay: $$A(t) = A_0 e^{-kt}$$ where $A_0$ is the initial amount, $k$ is the decay constant, and $t$ is time.
3. **Find decay constant $k$ for Sample 1:**
$$400 = 800 e^{-k \times 1}$$
Divide both sides by 800:
$$\frac{400}{800} = e^{-k}$$
$$\frac{1}{2} = e^{-k}$$
Taking natural logarithm:
$$\ln\left(\frac{1}{2}\right) = -k$$
$$-\ln 2 = -k$$
$$k = \ln 2 \approx 0.693$$
4. **Find decay constant $k$ for Sample 2:**
$$800 = 1000 e^{-k \times 1}$$
Divide both sides by 1000:
$$\frac{800}{1000} = e^{-k}$$
$$0.8 = e^{-k}$$
Taking natural logarithm:
$$\ln(0.8) = -k$$
$$k = -\ln(0.8) \approx -(-0.2231) = 0.2231$$
5. **Compare decay constants:**
Sample 1 decay constant $k \approx 0.693$.
Sample 2 decay constant $k \approx 0.2231$.
6. **Interpretation:** A larger decay constant means faster decay. Since Sample 1 has a larger $k$, it decays faster than Sample 2.
7. **Conclusion:** The claim that Sample 2 decreases more rapidly is incorrect. Sample 1 decreases more rapidly.
**Final answer:** Sample 1 decays faster because its decay constant is larger ($k \approx 0.693$) compared to Sample 2 ($k \approx 0.2231$).
Radioactive Decay C2Eaad
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.