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The half-life of .^198Au is 2.7 days. C...

The half-life of ` .^198Au` is `2.7 days`. Calculate (a) the decay constant, (b) the average-life and (c) the activity of `1.00 mg` of `.^198Au`. Take atomic weight of `.^198Au` to be `198 g mol^(-1)`.

Text Solution

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The half-life and the decay constant are related as
` T_(1//2)=(In2)/(lambda)=(0.693)/(lambda)` or `lambda=(0.693)/(t_(1//2))=(0.693)/(2.7 days)`
`A=lambda N=(2.9xx10^(-6)s^(-1))(3.03xx10^(18))`
`=8.8xx10^(12)` distntegrations `s^(-1)`
`=(8.8 xx10^(12))/(3.7xx10^(10)) Ci=140 Ci`.
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