NO they have same number of protons. But neutrons are different.
26 protons
Not; the number of protons in isotopes is identical; only the number of neutrons is different.
The answer you are looking for is "isotopes" HOWEVER, please note you CAN NOT HAVE 2 elements with the same number of PROTONS. This is because the number of protons DEFINES an element. Isotopes are the SAME element but with differing numbers of neutrons.
Isotopes differ by the number of protons.
This statement is incorrect. Isotopes of an element have the same number of protons but differ in their number of neutrons. Rubidium, specifically, has two stable isotopes: Rb-85 and Rb-87, which both have 37 protons but different numbers of neutrons.
By the numbers of protons
All the isotopes of neptunium has 93 protons.
All the isotopes of actinium has 89 protons.
All the isotopes of neptunium has 93 protons.
All the isotopes of curium have 96 protons.
All the isotopes of actinium has 89 protons.
Isotopes of an element have the same numbers of protons in the nucleus (and corresponding electrons). It's not so much "can have", as "do have". It's just a different number of neutrons that makes a different isotope.