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Maksim231197 [3]
3 years ago
14

1. A 50 gram sample of a radioisotope decays to 12.5 grams in 14.4 seconds. What is

Chemistry
2 answers:
stiv31 [10]3 years ago
5 0

Answer:

Half life = 7.2 seconds

Explanation:

from \: decay \: equation \\ 2.303 log( \frac{n.}{nt} )  = kt \\ 2.303 log( \frac{50}{12.5} )  = k \times 14.4 \\ k =  \frac{2.303 log( \frac{50}{12.5} )}{14.4}  \\ k = 0.096288 {s}^{ - 1}  \\ since \: half \: life =  \frac{ ln(2) }{k}  \\ half \: life  =   \frac{ ln(2) }{0.096288}  \\ half \: life = 7.2 \: seconds

sp2606 [1]3 years ago
3 0
14.2 because basically you just divide it by 2 which would be half of it

That will work with all of those problems

So if it’s is a quarter of an isotope you’d divide by 4
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