Isotopes are atoms that contain the same number of protons but a different number of neutrons in their nuclei. based on this information, which statement about isotopes is true? a. isotopes are atoms of the same element. b. isotopes are atoms that have the same mass number. c. isotopes are atoms of different elements that have similar chemical and physical properties. d. isotopes are atoms of different elements that belong to the same family on the periodic table.