The correct answer is Zn.Zinc is a chemical element with the symbol Zn and atomic number 30.Atomic Number is defined as the number of protons in the nucleus of an element.It is used to determine the characteristics of an element and it is also referred to for placing an element in the Periodic Table.The Atomic Number of Zinc (Zn) is 30 whereas the Mass Number is 65 i.e. it has 35 neutrons.It is the first element in group 12 (IIB) of the periodic table.Zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size.Additional InformationElementSymbolAtomic Number (Z)IronFe26CobaltCo27NickelNi28