Carbon-14 has a half-life of 5730 years. How much of a 144 g sample of carbon-14 will remain after 1719 years?

1 Answer
Aug 5, 2017

The mass remaining is #=117g#

Explanation:

The half life of carbon-#14# is #t_(1/2)=5730y#

This means that in #5730y#, the initial amount of carbon#-14# will be halved

The radioactive constant is

#lambda=ln2/t_(1/2)=ln2/5730=0.000121#

The fundamental decay equation is

#m=m_0e^(-lambdat)#

The initial amount of carbon#-14# is #m_0=144g#

The time is #t=1719y#

Therefore

#m=144*e^(-0.000121*1719)=144*e^-0.208=117g#