Question

the isotopic abundance of C-12 and c-14 is 98% and 2% by mass respectively. what would be the no. of atoms of c-14 isotope in 12g carbon sample?

Answer 1

mols C = 12g/12 = 1
1 mol contains 6.02E23 atoms.
98% of those will be C-12 and 2% will be C-14; therefore, number atoms C-14 = 6.02E23 x 0.02 = ?

Answer 2

1.02*1022