Half-life of carbon-14 is 5730 years. A piece of wood that contained 0.200g of Carbon-14 when it was alive now contains 0.0125g of Carbon-14. How old is the piece of wood? 5730 years old 11460 years old 17190 years old 22920 years old?

Question

3906 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-09-11T19:48:08

22920

#(1/2)^(t/5730)(I)=A#

I = initial amount, A = current amount, t = years

I=0.200g, A= 0.0125g, solve for t

#(1/2)^(t/5730)(0.200)=0.0125#

#(1/2)^(t/5730)=0.625#

#log_(1/2)((1/2)^(t/5730))=log_(1/2)0.0625#

#t/5730=4#

#t=22920#