Question

Which of the following sets represents a pair of isotopes?

14C and 14N

206Pb and 208Pb

O2 and O3

32S and 32S2-

Answer 1

isotopes are two common elements having the same number of protons but different in the number of neutrons. another way to look at it is that they are the same elements but they have different atomic weights

since it's two elements then that cancels out the choice 14C and 14N because those are different elements

O2 and O3 differ in the number of moles (meaning the quantity of oxygen atoms..not protons or neutrons) so that cancels choice C

choice D shows the same atomic weights 32 for S and just differ in the number of moles as well

therefore the answer is B. according to deduction and because 206 Pb and 208 Pb differ in atomic masses