CUET · CHEMISTRY · PYQ PAPER 2023
The isotope \({ }^{42} K\) has a half life of about 12 hours. What fraction of the initial concentration remains after 48 hours?
- A 1/4
- B 1/8
- C 1/12
- D 1/16
Answer & Solution
Correct Answer
(D) 1/16
Step-by-step Solution
Detailed explanation
\( n = t / T_{1/2} = 48 \text{ h} / 12 \text{ h} = 4 \) \( \text{Fraction remaining} = (1/2)^n = (1/2)^4 = 1/16 \)
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