Question

Carbon has different isotopes. What is different between an atom of 12C and an atom of 13C?

A. number of protons in the nucleus

B. number of neutrons in the nucleus

C. number of electrons in the atom

D. number of protons and electrons in the atom

Answer 1

Isotopes are atoms of the same element with the same number of protons and  electrons and different number of neutrons. Hence, the difference between atom of 12C and an atom of 13C is the number of neutrons in the nucleus.

Ans: B