Carbon-14 is used to determine the age of ancient objects. If a sample today contains 0.060 g of carbon-14, how much carbon-14 m
2 answers:
Answer : 0.239 gram of carbon-14 must have been present in the sample 11,430 years ago.
Solution : Given,
As we know that the radioactive decays follow first order kinetics.
First, we have to calculate the rate constant of carbon-14.
Formula used :
Now put the value of half-life, we get the value of rate constant.
Now we have to calculate the original amount of carbon-14.
The expression for rate law for first order kinetics is given by :
where,
k = rate constant =
t = time taken for decay process = 11430 years
a = initial amount of the carbon-14 = ?
a - x = amount left after decay process = 0.060 g
Putting values in above equation, we get the value of initial amount of carbon-14.
Therefore, 0.239 gram of carbon-14 must have been present in the sample 11,430 years ago.
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