1: copper has an atomic number of 29 that means there are 29 protons in the nucleus of each upper atom. that's what the atomic nuber is; the number of protons in an atom of a ceartain element if one copper atom contains 29 protons, how many electrons are there in 4 atoms of copper? 2: copper has an atomic number of 29 that means there are 29 protons in the nucleus of each upper atom. that's what the atomic nuber is; the number of protons in an atom of a ceartain element if one copper atom contains 29 protons, how many copper atoms could you make out of 87 protons?