WBJEE · Physics · Nuclear Physics
Radon- 222 has a half-life of 3.8 days. If one starts with \(0.064 \mathrm{kg}\) of radon-222, the quantity of radon- 222 left after 19 days will be
- A \(0.002 \mathrm{kg}\)
- B \(0.062 \mathrm{kg}\)
- C \(0.032 \mathrm{kg}\)
- D \(0.024 \mathrm{kg}\)
Answer & Solution
Correct Answer
(A) \(0.002 \mathrm{kg}\)
Step-by-step Solution
Detailed explanation
Half life of radon \(=3 \cdot 8\) days Total half-lives in 19 days \(\begin{array}{l} =\frac{19}{3 \cdot 8} \\ =\frac{190}{38} \end{array}\) \(=5\) half-lives Initially mass of radon \(=0.064 \mathrm{kg}\)…
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