Periodic Table Notes
Group 2: Akaline Earth Metals
2 electrons in the outer shell. Often reactive with oxygen Family. Less reactive than alkali metals though. Key Properties: Softer than other metals. React with water 2 valance electrons. Easily lose electrons.
Group 17: Halogens
All are non-metals. Very reactive. Often bonded with elements from group 1. Key Properies: Toxic, Colored, Poor Conductors, Low Melting and Boiling Points.
Group 16: Oxygen Family
Contain metals, metaliods, and non metals. Reactive: Generally with alkaline Earth Metals.
Group 14 and 15: Carbon Family and Nitrogen Family
Contains metals, metaliods, and non metals. Also called mixed groups.
Groups (Families) of elements
Elements arranged in columns with similar chemical properties
Group 18: Noble Gas Family
Exist as gases. All are nonmetals. Inert. Not reactive with other elements because their valence shell is full. 8 electrons in the outer shell= full. Hydrogen has 2 electrons which makes a full shell. Key Properties: Stable, colorless, odorless, inert.
Properties of Metals
Found on left side of the Periodic Table. Metals are good conductors of heat and electricity. Shiny (luster). Ductile (can be pulled into thin wires). Malleable (can be pounded into thin sheets). A chemical property of metal is its reaction with water which results in rust/ corrosion. Oxidation.
Properties of Nonmetals
Found on the right hand side of the Periodic Table. Non metals are poor conductors of heat and electricity. Not ductile or malleable. Solid non metals are brittle and break easily. They are dull. Many nonmetals are gases.
Groups 3-12: Transition Metals
Good conductors of heat and electricity. Used for wiring, tools, jewelry, decorative metal work, etc. Valence electrons (and thus oxidation numbers) can vary. For instance Cu can have 1, 2, 3, 4 valence electrons depending on the version of Cu. Can bond with many elements in a variety of shapes
Group 1 Alkali Metals
Hydrogen is not a member, it is a non- metal. 1 electron in the outershell. Often react with the Halogen Family (7 valance electrons). Very reactive, especially with water. Key properties: Soft, tarnish rapidlly, low melting point, low densities Violently reactive.
Who developed the Periodic Table?
In 1871 Dimitri Mendeleev organized information about all known elements in a periodic table, based on similar physical and chemical properties. It became known as the periodic table of the elements. The modern periodic table contains 111 different kinds of elements.
Rare Earth Metals
Lathanide Series, Actinides Series. Some are radioactive. The rare earths are silver, silvery- white, greyish metals. Conduct electricity.
Metalloids
Located between Metals and Nonmetals of the Periodic Table. Metalloids (metal like) have properties of both metals and non metals. They are solids that can be shiny or dull, ductile and malleable, conduct heat and electricity better than nonmetals but not as well as metals. Act as semiconductors. Used in computer industry.
Group 13: Boron Family
Most are metals, Boron is a metalliod.
Periods
The first element in a period is always an extremely active solid. The last element in a period id always an inactive gas. As you travel to the right across a period, you increase the number of protons in the nucleus by 1.
Hydrogen
The hydrogen square its a top family A1, but it is not a member of that family. Hydrogen is in a class of its own. It has one proton and one electron in its one and only energy level. Hydrogen only needs 2 electrons to fill up its valence shell.
