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3 years ago

Carbon-14 has a half-life of 5715 years. It is used to determine the age of

Chemistry

1 answer:

Radda [10]3 years ago

6 0

The sample of Carbon-14 after 28,575 years=0.001875 mg

<h3>Further explanation</h3>

General formulas used in decay:

$\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{T/t\frac{1}{2} }}}$

T = duration of decay

t 1/2 = half-life

N₀ = the number of initial radioactive atoms

Nt = the number of radioactive atoms left after decaying during T time

Carbon-14 has a half-life of 5715 years, so t1/2=5715 years

A sample today contains 0.060 mg of carbon-14, so No=0.06 mg, then :

$\tt Nt=0.06(\dfrac{1}{2})^{28575/5715}\\\\Nt=0.06(\dfrac{1}{2})^5\\\\Nt=0.001875~mg$

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