(A) The number of half-lives $(n)$ is calculated as $n = \frac{\text{Total time}}{\text{Half-life}} = \frac{40 \ days}{20 \ days} = 2$. The amount of

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(A) The number of half-lives $(n)$ is calculated as $n = \frac{\text{Total time}}{\text{Half-life}} = \frac{40 \ days}{20 \ days} = 2$. The amount of substance remaining $(N)$ is given by the formula $N = \frac{N_0}{2^n}$,where $N_0$ is the initial amount. Substituting the values,$N = \frac{100 \ g}{2^2} = \frac{100}{4} = 25 \ g$.

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

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$A$ radioactive isotope has a half-life of $20 \ days$. If $100 \ g$ of the substance is taken,the weight of the isotope remaining after $40 \ days$ is ......... $g$.

A
$25$
B
$2.5$
C
$60$
D
$40$

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Nuclear Chemistry

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Rate of decay and Half-life

If $n_t$ number of radioatoms are present at time $t$, the following expression will be a constant:

MediumWBJEE 2009

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The rate constant for a radioactive decay reaction is $\lambda$. The average life is represented by:

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For $Ra^{226}$,the $t_{1/2}$ is $1620 \ years$. From $0.001 \ g$ of $Ra$,how many $\alpha$-particles are released per $min$?

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What is the half-life of a radioactive substance if $87.5\%$ of any given amount of the substance disintegrates in $40 \, min$?

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The unit of the decay constant for radioactive disintegration is:

MediumMHT CET 2011

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$A$ radioactive isotope has a half-life of $20 \ days$. If $100 \ g$ of the substance is taken,the weight of the isotope remaining after $40 \ days$ is ......... $g$.

Similar Questions

If $n_t$ number of radioatoms are present at time $t$, the following expression will be a constant:

The rate constant for a radioactive decay reaction is $\lambda$. The average life is represented by:

For $Ra^{226}$,the $t_{1/2}$ is $1620 \ years$. From $0.001 \ g$ of $Ra$,how many $\alpha$-particles are released per $min$?

What is the half-life of a radioactive substance if $87.5\%$ of any given amount of the substance disintegrates in $40 \, min$?

The unit of the decay constant for radioactive disintegration is:

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