(B) The total time elapsed from February $1$ to July $1$ is $28 + 31 + 30 + 31 + 30 = 150 \, days$.Using the radioactive decay formula: $N = N_0 (1/2)

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(B) The total time elapsed from February $1$ to July $1$ is $28 + 31 + 30 + 31 + 30 = 150 \, days$.Using the radioactive decay formula: $N = N_0 (1/2)^n$,where $n$ is the number of half-lives.$0.25 = 8 \times (1/2)^n$$(1/2)^n = 0.25 / 8 = 1 / 32 = (1/2)^5$.Therefore,$n = 5$.Since $n = \text{total time} / t_{1/2}$,we have $5 = 150 / t_{1/2}$.$t_{1/2} = 150 / 5 = 30 \, days$.

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

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$8 \, g$ of the radioactive isotope,cesium$-137$ were collected on February $1$ and kept in a sealed tube. On July $1$,it was found that only $0.25 \, g$ of it remained. So the half-life period of the isotope is ....... $days$.

A
$37.5$
B
$30$
C
$25$
D
$50$

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Nuclear Chemistry

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Rate of decay and Half-life

$t_{1/2}$ of $^{232}Th$ is $1.39 \times 10^{10} \ \text{years}$. Calculate the number of $\alpha$-particles emitted by $1.0 \ \text{g}$ of $^{232}Th$ per second.

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$A$ radioactive isotope has a $t_{1/2}$ of $10 \ days$. If today $125 \ g$ of it is left,what was its weight $40 \ days$ earlier?

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$A$ certain nuclide has a half-life period of $30 \ minutes$. If a sample containing $600$ atoms is allowed to decay for $90 \ minutes$,how many atoms will remain?

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

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The half-life of $_{38}^{90}Sr$ is $20 \text{ years}$. If a sample having an initial activity of $8000 \text{ dis/min}$ is taken,what would be its activity after $80 \text{ years}$?

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$8 \, g$ of the radioactive isotope,cesium$-137$ were collected on February $1$ and kept in a sealed tube. On July $1$,it was found that only $0.25 \, g$ of it remained. So the half-life period of the isotope is ....... $days$.

Similar Questions

$t_{1/2}$ of $^{232}Th$ is $1.39 \times 10^{10} \ \text{years}$. Calculate the number of $\alpha$-particles emitted by $1.0 \ \text{g}$ of $^{232}Th$ per second.

$A$ radioactive isotope has a $t_{1/2}$ of $10 \ days$. If today $125 \ g$ of it is left,what was its weight $40 \ days$ earlier?

$A$ certain nuclide has a half-life period of $30 \ minutes$. If a sample containing $600$ atoms is allowed to decay for $90 \ minutes$,how many atoms will remain?

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

The half-life of $_{38}^{90}Sr$ is $20 \text{ years}$. If a sample having an initial activity of $8000 \text{ dis/min}$ is taken,what would be its activity after $80 \text{ years}$?

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