Explanation: Carbon has 3 isotopes. Carbon-12, Carbon-13, and Carbon-14 All of them have an atomic number of 6, which means all of them have 6 protons (if they had different numbers of protons, they'd be different elements). Since they all have 6 protons, in their elemental forms, they all have 6 electrons, too. Carbon-12: Atomic number: 6 Mass number: 12 protons: 6 electrons: 6 neutrons: 6 Carbon-13: Atomic number: 6 Mass number: 13 protons: 6 electrons: 6 neutrons: 7 Carbon-14: Atomic number: 6 Mass number: 14 protons: 6 electrons: 6 neutrons: 8