Atomic number:14

Group numbers:14

Period:3

Electronic configuration:[Ne] 3s² 3p²

Formal oxidation number:-4 +2 +4

Electronegativities:1.9

Atomic radius / pm:117.6

Relative atomic mass:28.0855 ± 0.0003

 

Silicon was discovered by Jöns Jacob Berzelius (SE) in 1824. The origin of the name comes from the Latin word silicis meaning flint. Amorphous form of silicon is brown powder; crystalline form has grey metallic appearance. The solid form is unreactive with oxygen, water and most acids. It dissolves in hot alkali. Silica dust is a moderately toxic acute irritant. Silicon makes up major portion of clay, granite, quartz (SiO2) and sand. Commercial production depends on a reaction between sand (SiO2) and carbon at a temperature of around 2200 °C. It is used in glass as silicon dioxide (SiO2). Silicon carbide (SiC) is one of the hardest substances known and used in polishing. Silicon is by far the more widely used semiconductor for electronics.

Density / g dm^-3:2329 (293 K)

 2525 (m.p.)

Molar volume / cm³mol^-1:12.06 (293 K)

 11.12 (m.p.)

Electrical resistivity / μΩcm:10 (20 °C)

Thermal conductivity / W m^-1K^-1:148

Melting point / °C:1414

Boiling point / °C:3265

Heat of fusion / kJ mol^-1:39.6

Heat of vaporization / kJ mol^-1:383.3

Heat of atomization / kJ mol^-1:451.29

1st ionization energy / kJ mol^-1:786.52

2nd ionization energy / kJ mol^-1:1577.15

3rd ionization energy / kJ mol^-1:3231.61

in the atmosphere / ppm:-

in the Earth's crust / ppm:267700

in the oceans / ppm:3