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2 years ago

The isotope Np-238 has a half life of 2.0 days if 96 grams of it were present on Monday how much will remain six days later

Chemistry

1 answer:

Neporo4naja [7]2 years ago

4 0

Answer:

12 grams

Explanation:

For any radioactive substance

the amount of substance left after n half life is given by = $x/2^n$

where x the original amount of substance.

____________________________________________

Half life of isotope Np-238 = 2 days

total no of days = 6

no of half life =total no of days/Half life of isotope Np-238 = 6/2 = 3

thus,

for our problem n = 3

initial amount of Np-238 = 96 grams

thus,

the amount of substance left after 3 half life = 96/2^3 = 96/8 = 12 grams.

Thus, 12 grams will be left after six days.

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Using integrated rate law for first order kinetics as:

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Where,

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$[A_0]$ is the initial concentration

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$-2.8\times \:10^{-3}t=\ln \left(\frac{91}{125}\right)$

$t=113\ min$

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