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What is the half-life ($T_{1/2}$) of a radioactive substance if its decay constant is $\lambda = 0.693 \text{ s}^{-1}$?
- A.$0.5 \text{ s}$
- B.$1.0 \text{ s}$
- C.$2.0 \text{ s}$
- D.$0.693 \text{ s}$
Show correct answer & step-by-step solution
Correct answer: B — $1.0 \text{ s}$
Solution
The half-life is given by . Using , we get .
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