In a uranium ore the ratio of U238 to Pb206 nuclei is 1:15. Evalute the age of ore, assuming Pb206 to be the final, initially only uranium was present (given ratio is of number of nuclei). (Half life= 4.5×109 years)
A
4.5×103 years
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
13.5×103 years
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
9×103 years
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
18×103 years
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution
The correct option is D18×103 years N=Noe−λt U⟶Pb t=0N00 t=tNN0−N 1 15
ratio No−NN=15 N0−N=15N 16N=No if No=16N=1 This means it has taken 4 half lives.