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Question
Decay constant of 197Hg is 0.017 h-1. What is its half-life?
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Solution
Given: λ = 0.017 h-1
To find: t1/2
Formula: `"t"_(1//2) = 0.693/lambda`
Calculation: `"t"_(1//2) = 0.693/lambda`
`= 0.693/(0.017 "h"^(-1))` = 40.77 h (by using log table)
Thus, the half-life of 197Hg is 40.77 h.
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