Metals
What are Metals? Metals are groups of elements found on the left side of the periodic table While every metal is unique, all metals share a common set of physical properties Examples of metals include: -- silver -- sodium -- mercury -- iron -- copper
Physical Properties of Metals The physical properties shared by all metals are: Shininess – most metals reflect light and appear “shiny” Malleability – the ability to be pounded into shapes -- most metals are malleable Ductility – the ability to be pulled or drawn into wires or sheets -- most metals are ductile Conductivity – the ability to carry an electric current -- most metals are good conductors Other metals share the property of magnetism, although not all metals are magnetic. . .
Chemical Properties of Metals The chemical properties of metals depend on the number of valence electrons in the metal Metals with one or two valence electrons are very reactive -- such as sodium, potassium, and magnesium Metals with many valence electrons can be almost completely unreactive -- such as gold and chromium Some metals react with air to form metal oxides, which wear away the metal -- the reaction and wearing away of metals is called corrosion -- this is how rust is formed
Mixtures of Metals Mixtures of metals are called alloys -- technically, an alloy is a solution of two solid metals Alloys are useful because they combine the best physical properties of two substances Examples of alloys include: Bronze – made of copper and tin Steel – made of iron, chromium, and vanadium
Metal Families On the periodic table, metals in groups or families have similar chemical properties. The groups, or families, of metals on the periodic table include: -- Alkali Metals -- Alkaline Earth Metals -- Transition Metals -- Mixed-Group Metals
Alkali Metals Metals in group 1 (I) on the far left of the periodic table are alkali metals -- hydrogen is in group 1, but is not considered a metal because of its physical properties so it is not included Alkali metals share the following characteristics -- insanely reactive, because they have 1 valence e- -- they are so reactive that they are never found alone in elements, only in compounds -- soft and shiny Examples include: -- sodium, found in salt -- lithium, used in batteries
Alkaline Earth Metals Alkaline Earth Metals are all the elements in group 2 (II) of the periodic table The properties shared by all alkaline earth metals are: -- very reactive (not as much as alkali metals) -- never found uncombined in nature -- grey/white in color -- hard to cut -- good conductors of electricity Examples of Alkaline Earth Metals include: -- calcium, essential in teeth and bones -- magnesium, which is used in flashbulbs
Transition Metals Transition metals include all elements in groups 3 – 12 of the periodic table Properties shared by transition metals include: -- being fairly stable and slow to react with air and water -- usually hard and shiny -- despite being in different groups, they all have similar numbers of valence electrons and share similar bonding patterns Examples of transition metals include: -- gold, silver, nickel, copper, iron These are what you usually think of as “metals”
Lanthanides and Actinides Lanthanides and actinides are like transition metals, but because they are in rows 6 and 7 of the periodic table, they have extra energy electrons and have slightly different properties, and are placed below the table Lanthanides are soft, malleable, shiny, and good conductors -- most lanthanides have similar chemical properties Actinides are usually very unstable -- the only “natural” actinides are thorium and uranium -- the rest are synthetic (man-made) -- many actinides are radioactive
Mixed-Group Metals Mixed-Group Metals are those in groups 13 – 16 (III – VI) of the periodic table -- they are located between the transition metals and the metalloids Properties shared by mixed-group metals include: -- low reactivity Examples of Mixed-group metals include: -- Aluminum, used in cans and automobiles -- Lead, which used to be used in pipes