# Chemistry

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The half-life for radioactive decay of 14C is 5730 years (it emits β-particles with energy
of 0.16 MeV). An archaeological sample contained wood that had only 72% of the 14C
found in living trees. What is its age?

• Chemistry -

k = 0.693/t1/2
Calculate k and substitute into the equation below.

ln(No/N) = kt
I would make up a convenient number for No, say 100, which makes N just 72% of that or 72. Calculate t.

• Chemistry -

thanks DrBob :)

• Chemistry -

2716 years

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