An atom of boron has three valence electrons. The valence electrons of boron occupy the second orbit around the nucleus of the boron atom. Thus, the boron atom has an electronic configuration of [He] 2s2 2p1.
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. Its density is 2.37 grams per cubic centimeters. It is a solid at room temperature.