Answer: element symbol : Cu.
Number of protons= 29
Number of electrons = 29
Explanation:
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons (i)
Atomic number is defined as the number of protons or number of electrons that are present in an atom in a neutral element.
Atomic number = Number of electrons = Number of protons (ii)
Given mass number = 65
Number of neutrons = 36
using (i) , Mass number = Number of protons + Number of neutrons
65= Number of protons + 36
Number of protons = 29
Using (ii) , Atomic number = Number of protons = Number of electrons = 29
Thus the element is copper with atomic number of 29 and element symbol is Cu.