The atomic number is 5. The atomic number gives the number of protons. Protons which have a positive charge are balanced by an equal number of electrons in a neutral atom. Boron number 5 has five protons and therefore as a neutral atom also has five electrons. Boron atomic number 5 has five electrons in its ground state. Commonly Boron will lose 3 electrons leaving 2 electrons in its most common ionic form.
