Periodic Trends:FAMILIES

Alkali Metals(Group 1)

- do not occur elementally in nature - stored under kerosene or other hydrocarbon solvent because they react with water vapor or oxygen in air - form water-soluble bases - are strong reducing agents - are good conductors of electricity and heat - are ductile, malleable, and soft enough to be cut with a knife - have a silvery luster, low density, and a low melting point

Alkaline Earth Metals (Group 2)

- do not occur elementally in nature - occur most commonly as carbonates, phosphates, silicates, and sulfates - occur naturally as compounds that are either insoluble or only slightly soluble in water - are less reactive than alkali metals - primarily form ionic compounds - react w/water to form bases and hydrogen gas - are good conductors of heat and electricity - are ductile and malleable - have a silvery luster - include the naturally radioactive element radium

Transition Metals (Groups 3-12)

- are usually harder and more brittle than metals in groups 1 and 2 - have higher melting and boiling points than metals in groups 1 and 2 - are good conductors of heat and electricity - are malleable and ductile - have a silvery luster, except copper and gold - include radioactive elements 89 through 109 - include mercury, the only metal that is liquid at room temperature - have chemical properties that tend to differ from each other - often form colored compounds

Boron Family(Group 13)

- do not occur elementally in nature - are scarce in nature (except Al, which is the most abundant metallic element) - are metallic (except B, which is a solid metalloid) - are soft and have low melting points (except B, which is hard & has a high melting point) - are chemically reactive at moderate temperatures (except boron)

Carbon Family(Group 14)

-vary greatly in both physical and chemical properties - occur in nature in both combined and elemental forms - are relatively unreactive - tend to form covalent compounds (tin and lead also form ionic compounds)

Nitrogen Family(Group 15)

-consists of two nonmetals (N and P), two metalloids (As and Sb), and one metal (Bi) - nitrogen is most commonly found as atmospheric N2, phosphorus as phosphate rock, and arsenic, antimony, and bismuth as sulfides or oxides; antimony and bismuth are also found elementally- have five valence electrons - tend to form covalent compounds, most commonly with oxidation numbers of +3 or +5 - are solids at room temperature, except nitrogen

Oxygen Family(Group 15)

- occur elementally in nature and in combined states - consists of three nonmetals (oxygen, sulfur, and selenium), one metalloid (tellurium), and one metal (polonium) - tend to form covalent compounds with other elements - tend to exist as diatomic and polyatomic molecules, such as O2, O3, S6, S8, and Se8

Halogen Family(Group 17)

- are nonmetals and occur in combined form in nature - found in the rocks of Earth's crust and dissolved in sea water - exist at room temperature as a gas (F2 and Cl2), a liquid (Br2), and a solid (I2 and At) - have seven valence electrons - are reactive, with fluorine being the most reactive of all nonmetals

Noble Gases(Group 18)

- not reactive - have a full outer energy level - are all gases - are all nonmetals