Question

You have 360 million parent atoms of a radioactive isotope. If time passes and you end up with ____ parent atoms and ____ daughter atoms and the half-life is 2,500 years old.

How old is the sample?

A. 315,000,000 ; 45,000,000 ; 7,500 years

B. 11,250,000 ; 348,750,000 ; 12,500 years

C. 270,000,000 ; 90,000,000 ; 2,500 years

D. 5493 ; 359,994,507 ; 10,000 years

Answer 1

B. 11,250,000 ; 348,750,000 ; 12,500 years.

parent isotope has 360000000 atoms. after first half live 180000000 parents atoms will left and 180000000 atoms of daughter atoms form. after 2nd half life 90000000 parents atoms will left and time passed will be 5000 years. after 3rd half life 45000000 parents atoms will left and time will be 7500 years. after 4th half life 22500000 parent atoms left and age will be 10000 years. after 5th half life, 11250000 parent atoms left and the age will be 12500 years.