2) Element symbol: B
 

3) Number of electrons, protons, and neutrons: 5 electron, 5 proton, 5 neutrons
 

4) Atomic number: 5
 

5) Atomic mass: 10.18
 

6) Characteristics:

Pure crystalline boron is a black, lustrous, semiconductor; i.e., it conducts electricity like a metal at high temperatures and is almost an insulator at low temperatures.
 

7)

History:

Compounds of boron, notably borax, have been known since early times. But the pure element was prepared in 1808 by Joseph Gay - Lussac and Baron Louis Thenard (1777-1857) in France and independently by Sir Humphry Davy in England.

Three things made from the element:

- used in cleaning compounds

- used in glass and ceramics

- used in fertilizers

- used in paper and paints

- used in fire retardants
 

8) Isotopes:

In nature, boron consists of a mixture of two stable isotopes--boron-10 (19.8 percent) and boron-11 (80.2 percent); slight variations in this proportion produce a range of +/-0.003 in the atomic weight. Because of the high thermal neutron cross section of the rarer isotope boron-10 (3,836 barns), boron and some of its compounds have been used as neutron shields.
 

9) At red heat, boron combines directly with nitrogen to form nitride, and with oxygen to form oxide. With metals it forms borides, such as magnesium boride.
 

10) Boron melts at about 2180 °C (about 3956 °F) and boils at about 3650 °C (about 6602 °F).