Question

How are isotopes of the same element alike? different?

Answer 1

Simply, isotopes are two or more forms of the same element that contain the same number of protons (or proton number) but with different nucleon number.
For example the regular Carbon atom has a proton number of 6 and a neutron number of 6. (called Carbon-12) while another form of Carbon (which is its isotope) Carbon -13 has a proton number of 6 and a neutron number of 7.
They are the same because they have the same proton number they have the same ...

Answer 2

Isotopes usually share the same chemical properties

Answer 3

But have different mass weight