2) Element symbol: Si
 

3) Number of electrons, protons, and neutrons: 14 electron, 14 proton, 14 neutrons
 

4) Atomic number: 14
 

5) Atomic mass: 28.0855
 

6) Characteristics:

Silicon usually appears as a brown amorphous powder or gray-black crystals.
 

7)

History:

Silicon was first isolated from its compounds in 1823 by the Swedish chemist Baron Jöns Jakob Berzelius.

Three things made from the element:

Silicon in used in the steel industry as a constituent of silicon - steel alloys.

In steel making, molten steel is deoxidized by the addition of small amounts of silicon; ordinary steel contains less than .03 % of silicon. Silicon steel, which contains 2.5 to 4 % silicon, is used in making the cores of electrical transformers because the alloy exhibits low hystersis.

A steel alloy, known as duriron, containing about 15% silicon, is hard, brittle, and resistant to corrosion; during is used in industrial equipment that comes in contact with corrosive chemicals. Silicon is also used as alloy in

- copper

- brass

- bronze
 

8) Isotopes:

Three stable isotopes of silicon are known: silicon-28, which makes up 92.21 percent of the element in nature; silicon-29, 4.70 percent; and silicon-30, 3.09 percent. Five radioactive isotopes are known.
 

9) Silicon is not attracted by nitric, hydrochloric, or sulfuric acids, but it dissolves in hydrofluoric acid, forming the gas, silicon tetrafluoride. It dissolves in sodium silicate and hydrogen gas. At ordinary temperatures, silicon in imperious to air, but at high temperatures, it reacts with oxygen, forming a layer of silica that does not react further. At high temperatures it also reacts with nitrogen and chlorine, respectively.
 

10) Silicon melts at about 1410 °C (about 2570 °F) and boils at about 2355 °C (about 4271 °F).