How can two atoms of the same chemical element be different?
A.
They may be different allotropes of the element. Each allotrope of the same element has a different number of neutrons.
B.
They may be different isotopes of the element. Each isotope of the same element has a different number of electrons.
C.
They may be different isotopes of the element. Each isotope of the same element has a different number of neutrons.
D.
They may be different allotropes of the element. Each allotrope of the same element has a different number of electrons.