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crimeas [40]
3 years ago
12

The radioisotope radon-222 has a half-life of 3.8 days. How much of a 73.9-g sample of radon- (3 222 would be left after approxi

mately 23 days?​
Chemistry
1 answer:
Novay_Z [31]3 years ago
6 0

Answer:

1.115 g

Explanation:

Applying,

R = R'2^{n/t}................... Equation 1

Where R = original sample of radon-222, R' = sample of radon-222 left after decay, n = Total time, t = half-life.

make R' the subject of the equation

R' = R/(2^{n/t})............... Equation 2

From the question,

Given: R = 73.9 g, n = 23 days, t = 3.8 days.

Substitute these values into equation 2

R' = 73.9/(2^{23/3.8})

R' = 73.9/2^{6.05}

R' = 1.115 g

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