how are isotopes similar and different?

Question

please help
i dont understand this.
thanks

Answer 1

This isn't too hard; the difference between isotopes is just the number of neutrons in the neucleus. The number of protons and electrons is the same as for the regular element.

When the number of neutrons is changed it is still the same element, the atomic number will be the same, but atomic weight will be different, chemistry and reactions will be the same. The presence of isotopes is the reason for the strange atomic weights for many elements; as the atomic weights are weighted averages for all the isotopes present.

Answer 2

Isotopes are any of the several different forms of an element each having different atomic mass (mass number). Isotopes of an element have the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleons—the number of protons plus neutrons.