Question

If the half life is 5700 years, how do you find the percentage of original carbon-14 that remains in a sample after 2476 years have passed?

Answer 1

Well, if the half-life of

14C is 5700

years, then that means after

5700

years have happened, there will be half of the original amount, i.e.

50%

of the original amount of

14C left.

So, after

2476

years, the sample of

14

C

has evolved:

2476

5700

≈43.4% of a half-life

A rule to remember is that if

n

is the number of half-lives elapsed, there will be

1002n%

of the original amount of substance remaining. For the source of this information, click here.

So here,

n=43.4%=0.434

. Therefore, there will be

10020.434≈1001.35≈74.1% of the original amount remaining.