According to Data,
Mass Number = 65
# of Neutrons = 35
As we know,
Mass Number = # of protons + # of Neutrons
Solving for # of protons,
# of protons = Mass Number - # of Neutrons
Putting values,
# of Protons = 65 -35
# of protons = 30
As,
# of protons is the atomic number, so element with atomic number 30 is Zinc.
The cation derived from it has 28 electrons,
So, Zinc having 30 electron will be left with two extra protons, and each proton has +1 charge.
Result:
Zn²⁺