Question: how many protons and electrons does potassium ion have?
Answer: A potassium ion, K+ has an atomic number of 19 and a mass number of 39 So there are 19 protons and 39-19 = 20 neutrons. To become a positive ion it looses its valence electron with its valence shell and becomes K+ by achieving the configuration of 2,8,8,1 with 3 energy levels/shells.