(B) The radioactive decay follows the relation: $\frac{N}{N_o} = (\frac{1}{2})^n$,where $n$ is the number of half-lives.Given $\frac{N}{N_o} = \frac{1

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(B) The radioactive decay follows the relation: $\frac{N}{N_o} = (\frac{1}{2})^n$,where $n$ is the number of half-lives.Given $\frac{N}{N_o} = \frac{1}{8}$,we have $(\frac{1}{2})^n = \frac{1}{8} = (\frac{1}{2})^3$.Therefore,$n = 3$.The total time $t$ is given by $t = n \times t_{1/2}$.Given $t_{1/2} = 20 \ \text{minutes}$,so $t = 3 \times 20 \ \text{minutes} = 60 \ \text{minutes}$.

Class 12 Chemistry Nuclear Chemistry Rate of decay and Half-life

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$A$ radioactive element has a half-life of $20 \ \text{minutes}$. How much time should elapse before the element is reduced to $\frac{1}{8}$th of the original mass? (Answer in $\text{minutes}$)

A
$40$
B
$60$
C
$80$
D
$160$

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Nuclear Chemistry

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Rate of decay and Half-life

$1.0 \, g$ of a radioactive isotope was found to reduce to $125 \, mg$ after $24 \, hours$. The half-life of the isotope is $....... \, hours$.

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The decay of a radioactive element follows first-order kinetics. As a result:

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The decay constant of a radioactive element is $3 \times 10^{-6} \ min^{-1}$. Its half-life is

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The half-life of $1 \ g$ of a radioactive sample is $9 \ hours$. The radioactive decay obeys first-order kinetics. The time required for the original sample to reduce to $0.2 \ g$ is .......... $hours$.

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What is the half-life period of a nucleus in $days$ if at the end of $4.2$ $days$,$N = 0.798 \ N_0$?

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$A$ radioactive element has a half-life of $20 \ \text{minutes}$. How much time should elapse before the element is reduced to $\frac{1}{8}$th of the original mass? (Answer in $\text{minutes}$)

Similar Questions

$1.0 \, g$ of a radioactive isotope was found to reduce to $125 \, mg$ after $24 \, hours$. The half-life of the isotope is $....... \, hours$.

The decay of a radioactive element follows first-order kinetics. As a result:

The decay constant of a radioactive element is $3 \times 10^{-6} \ min^{-1}$. Its half-life is

The half-life of $1 \ g$ of a radioactive sample is $9 \ hours$. The radioactive decay obeys first-order kinetics. The time required for the original sample to reduce to $0.2 \ g$ is .......... $hours$.

What is the half-life period of a nucleus in $days$ if at the end of $4.2$ $days$,$N = 0.798 \ N_0$?

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