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german
1 year ago
8

Nuclear decay occurs according to first-order kinetics. How long will it take for a sample of radon-218 to decay from 99 grams t

o 0. 50 grams? the half-life of radon-218 is 35 milliseconds.
Physics
1 answer:
dedylja [7]1 year ago
4 0

It will take 267 milliseconds for a sample of radon-218 to decay from 99 grams to 0. 50 grams.

We know that half life of a first order reaction is given by: t_{1/2} = 0.693/k

where k = rate of reaction

Given half life = 35 milliseconds

So from this we get k = 0.0198

Now we know that rate of first order reaction is given by: kt= 2.303 * log(R'/R)

where t= time

R'= initial amount = 99 g

R= final amount= 0.50 g

k= rate of reaction = 0.0198

Putting values of these in above equation we get t=267 milliseconds.

i.e. It will take 267 milliseconds for a sample of radon-218 to decay from 99 grams to 0. 50 grams.

To know more about radioactivity visit:

brainly.com/question/20039004

#SPJ4

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