Chemical Families (rachelle's group)

The vertical columns in the periodic table are known as groups or chemical families. There are five groups : Alkali Metals, Alkaline Earth Metals, Transition Metals, Halogens and Noble Gases. Elements in the same chemical family have similar physical and chemical properties.

Alkali Metals: Elements in the first column (Li, Na, K, Rb, Cs, Fr). Notice that Hydrogen isn't included because it is considered to be a separate group on its own. These elements are highly reactive (reactivity increases as you go down the group), have low melting points (below 200 C), low ionization energies (production of ions), low electronegatives (tendency to attract electrons) and can be cut with a knife.

Alkaline Earth Metals: Elements in the second column (Be, Mg, Ca, Sr, Ba, Ra). Their outer shells contain two electrons, they have low electronegatives, are less reactive than alkali metals, react with water and will burn if heated.

Transition Metals: They are the 38 elements in groups 3-12 of the periodic table. They are very hard, have high melting and boiling points, low ionization energies, high electrical conductivity and are malleable (able to be shaped and bent).

Halogens: Elements in group 17 of the periodic table (F, Cl, Br, I, At). they are non-metals that are highly reactive and have strong, unpleasant odors. Fluorine and chlorine are gases at room temperature, Bromine is a liquid and Iodine and Astatine are solids.

Noble Gases: Found in group 18 of the periodic table (He, Ne, Ar, Kr, Xe, Rn). They are the most stable and non-reactive elements. In addition, they are colorless and odorless gases at room temperature, have high ionization energies and low boiling points.