Question

Identify the isotope from the following pairs of atoms.

a.
C-12, C-13

b.
Na-23, Na-23

c.
All of the above

Answer 1

Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons, resulting in different atomic masses.

a. C-12 and C-13 are isotopes of carbon. C-12 has 6 protons and 6 neutrons, while C-13 has 6 protons and 7 neutrons.

b. Na-23 and Na-23 are not different isotopes; they are the same isotope of sodium, since both have the same number of protons and neutrons (11 protons and 12 neutrons).

c. Since only the pair in option a contains isotopes, the correct choice would be a.

So the answer is **a. C-12, C-13.**