The Carbon Family
The group with 4 valence electrons
Date discovered: unknown
Uses: solder, protection against radiation, batteries, bullets, corrosive, paint
Lead is a blueish-white metal with a melting point of 327.46 degrees Celsius and a boiling point of 1749 degrees Celsius. Its atomic number is 82 and atomic mass of 207.2 g.cm-3. It is very toxic and does not burn. It does not react with water or air and is heavy.
Density: 11.34 g.cm-3 at 20 degrees Celsius
Malleability: can be bent into shape
Conductivity: poor transition of heat and electricity
Softness: relatively soft
Tensile: can be stretched without breaking
Luster: shine or glow
Discovered: Jöns Jacob Berzelius
Uses: Silicons provides more resistance to the aluminum, magnesium, copper
The melting point of silicon is 1,410°C and the boiling point is 2,355°F (4,270°F). Its density is 2.33 grams per cubic centimeter. Silicon has a hardness of about 7 on the Mohs scale. The Mohs scale is a way of expressing the hardness of a material. It runs from 0 (for talc) to 10 (for diamond).
There is three naturally occurring isotopes of silicon: silicon-28, silicon-29, and silicon-30. Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the right of the element's name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope.