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The half-life period of an unstable isotope is the time taken for the
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22 Apr 2025, 03:06
22 Apr 2025, 03:06
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The half-life period of an unstable isotope is the time taken for the substance to decay to half of the original amount. If, in one hour, $6.35 \%$ of the original amount of an unstable isotope is remaining, find the approximate half-life time of the isotope correct to the nearest minute.
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Re: The half-life period of an unstable isotope is the time taken for the
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26 Apr 2025, 04:00
26 Apr 2025, 04:00
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\(\begin{aligned}
&\begin{aligned}
& 100 \xrightarrow{\text { It half - life }}-50 \stackrel{2^{\text {nd }} \text { half -life }}{\rightarrow} 25 \xrightarrow{3^{\text {rd }} \text { half-life }} 12.5 \xrightarrow[\rightarrow]{4^{\text {th }} \text { half life }} 6.25 \\
& \therefore 1 \text { hour }=4 \text { half }- \text { life } \\
& \therefore 1 \text { half }- \text { life }=\frac{1}{4} \text { hour }=15 \text { minutes. }
\end{aligned}\\
&\text { Thus, the correct answer is } 15 \text { minutes. }
\end{aligned}\)
&\begin{aligned}
& 100 \xrightarrow{\text { It half - life }}-50 \stackrel{2^{\text {nd }} \text { half -life }}{\rightarrow} 25 \xrightarrow{3^{\text {rd }} \text { half-life }} 12.5 \xrightarrow[\rightarrow]{4^{\text {th }} \text { half life }} 6.25 \\
& \therefore 1 \text { hour }=4 \text { half }- \text { life } \\
& \therefore 1 \text { half }- \text { life }=\frac{1}{4} \text { hour }=15 \text { minutes. }
\end{aligned}\\
&\text { Thus, the correct answer is } 15 \text { minutes. }
\end{aligned}\)
gmatclubot
Re: The half-life period of an unstable isotope is the time taken for the [#permalink]
26 Apr 2025, 04:00
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