Grouping Elements 12.2

Alkali Metals Group 1 1 electron in the outermost shell Soft silver metals with the exception of Hydrogen which is reactive gas Very reactive – Tend to combine violently with halogens to form salts One electron is lost, forming a positive ion Are not found uncombined in nature

Alkaline Earth Metals Group 2 elements Have 2 electrons in outermost shell Very reactive but not as reactive as alkali metals two electrons are harder to lose than one. Have higher density than Alkali metals

Transition Metals Groups 3-12 Less reactive than alkaline earth metals; atoms do not give away their electrons as easily as group 1 or 2 metals Tend to be shiny, more dense than group 1 or 2 metals and good conductors of heat and electricity Includes Lanthanides and actinides(radioactive)

Boron Group Group 13 Atoms are reactive – they combine easily with other elements Atoms have three electrons in outermost shell Aluminum is most common element

Carbon Group Group 14 Atoms have 4 electrons in outer level Reactivity varies among the elements in this group. Carbon atoms combine to form long chains

Nitrogen Group Group 15 Contains 5 electrons in the outermost shell Reactivity varies among elements Nitrogen is not very reactive and makes up about 80% of atmospheric air

Oxygen Group Group 16 Contains 6 electrons in outermost shell Elements are reactive and tend to gain electrons, creating negative ions

Halogens Group 17 Contain 7 electrons on outer shell Very reactive – tends to gain one electron, forming negative ions Elements tend to combine violently with alkali metals, forming salts Contain nonmetals that are only found combined with other elements in nature

Noble Gases Group 18 elements Has full outermost electron shell – do not need to lose or gain electrons for stability Elements are unreactive– they do not combine chemically with other elements