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Carbon Decay. Carbon -14 has a half-life of 5730 years. How long will it take for 200 grams to decay to 140 grams? Round your answer to two decimal places.

User Sedat
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Answer: It would take approximately 5730 years for 200 grams of carbon -14 to decay to 140 grams.

Explanation: Lets breakdown this into two parts.

Calculate the ratio of the final amount to the initial amounts:

final amount/initial amount

=140 grams/200 grams

=0.7

Determine the no. of half lives req to reach this ratio:

log(base1/2)(1/2)^(no. of half lives)= log (base 1/2 ) (0.7)

Number of half lives = log (base 1/2)(0.7)

= 0.5146

So, half life cannot be fraction. Therefore, it will take one half life for 200 grams of carbon -14 to decay to approximate 140 grams.

so it will take 5730 years to decay 140 grams.

User Fugogugo
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