number of electrons in boron
Boron has three valence electrons. It is in group 13. Outermost energy level is the the 3rd energy level and it has three electrons. Valence electrons are the electrons in the last energy level of an atom. You can also just look at the group number (13) and the second number is the number of valence electrons.
Boron is classified as a metalloid with brown color. Its atomic number is 5, so it has a total of five electrons revolving around the nucleus. It has six neutrons and five protons in the nucleus. The atomic weight of boron is 10.811 grams per mole. Boron has a high melting point of 3,767 degrees Fahrenheit and a boiling point of 7,232 degrees Fahrenheit.