How do two isotopes of the same element compare with each other?

A.They have the same number of protons but a different number of electrons.

B.They have the same mass number but a different number of protons.

C.They have the same mass number but a different number of neutrons.

D.They have the same number of protons but a different number of neutrons.

1 answer

(D)

in any atom the protons always equal the electrons, which is the atomic number.

The only thing left that can vary is the number of neutrons, which gives a different mass number (protons+neutrons)