Chapter 19, Section 1. Metals. Metals usually have common properties. Good conductors of heat Good conductors of electricity All but one (mercury) are Solid at room temperature Have Luster (reflect light) Are Malleable (can be hammered or rolled into sheets) - PowerPoint PPT Presentation
Chapter 19, Section 1
Chapter 19, Section 1MetalsMetals usually have common properties...Good conductors of heatGood conductors of electricityAll but one (mercury) are Solid at room temperatureHave Luster (reflect light)Are Malleable (can be hammered or rolled into sheets)Are Ductile (can be drawn into wires)Have 1-3 electrons in their outer energy level and typically form Ionic Bonds
Metallic BondingPositively charged metallic ions are surrounded by a cloud of electrons. The electrons move freely among many positively charged ions.
The idea of metallic bonding explains many of the properties of metals. For example, when a metal is hammered into a sheet or drawn into a wire, it does not break because the ions are in layers that slide past one another without losing their attraction to the electron cloud. Metals are also good conductors of electricity because the outer-level electrons are weakly held.3The Alkali MetalsGroup 1 of the periodic tableAre softer than most other metalsMost REACTIVE of all the metalsThey react rapidly with water and oxygenHave one electron in outer shellFrancium is extremely rare and radioactiveRadioactive element: is one in which the nucleus breaks down and gives off particles and energyThe Alkaline Earth MetalsGroup 2 of the periodic tableHave 2 electrons in their outer shellUsed in fireworks!Magnesium-bright whiteStrontium-RedTransition ElementsGroups 3-12Transition elements are the most familiar because they are found in nature as uncombined elements, unlike Group 1 & 2 elements which are less stable
Iron TriadIron, Cobalt, & NickelAll three of these elements are used in the process to create steel and other metal mixtures.Iron is the most widely used of all metals
Coinage MetalsCopper, Silver, & GoldGroup 11Were once used to make coinswhy not anymore?Were used to make coins because they are so stable and malleableMost coins now are made of nickel and copper
Gold and silver are too pricey to make coins with now8Inner Transition MetalsAtomic numbers 58-71Are called lanthanides because they follow the element lanthanumSome of the lanthanides are used by the movie industry and to produce the colors you see on your tv screen!Atomic numbers 90-103Are called actinide series because they follow the element actiniumAll of the actinides are radioactive & unstable
LanthanidesActinidesMetals in the CrustThe crust is the Earths hardened outer layerContains metals such as gold and copperMetals in the Earths crust that combined with other elements are found as ores.After an ore is mined from Earths crust, the rock is separated from the mineral.NonmetalsCh.19, Section 2Nonmetals
Usually gases or brittle solids at room temperatureRight of the metalloid line (staircase)Not malleableNot ductileDo not conduct electricityDo not conduct heatTypically not shiny (have no..)Luster
Opposites of metals!12If you could count all of the atoms on earth, which element do you think you would find 90% of the time?HydrogenHydrogenMost is found in the compound water
The word hydrogen is derived from the Greek term for water formingWhen water is broken down into its elements, hydrogen becomes a gas made up of diatomic moleculesDiatomic MoleculeConsists of two atoms of the same element in a covalent bond. Many elements exist in this way because they are too reactive to exist alone in nature.
Other examples:Chlorine,Fluorine, Bromine, and IodineGroup 17Very reactiveHave 7 valence electronsIf a halogen gains an electron from a metal.it forms a salt.Fluorine is the MOST chemically active of all elements!Have many uses.pg. 580 & 581you list 3 in your notesHalogensSublimationWhen a solid changes straight from a solid to a gas without first being a liquid!The noble GasesThe noble gases exist as isolated atoms.
They are stable because..why?
Their outermost energy level is full (with 8 electrons)The stability of noble gases is what makes them useful..Heliums light weight is what makes it useful in blimps and balloonsNeon and Argon are used in neon lights for advertisingKrypton is used in electric light bulbs to produce light in lasers for laser light showsLets look at these spectacular lights!Mixed GroupsCh.19, Section 3MetalloidsCan form ionic or covalent bondsHave metallic AND nonmetallic characteristicsTouch the stair step lineAre semiconductorsConduct an electric current under certain conditions, not all of the time or never!Other Groups:Boron, Carbon, Nitrogen, OxygenAllotropes(Dont confuse with Isotopes!)Different forms of the same element and have different molecular structures.
Read Page 586 and be able to talk about the allotropes of carbonSynthetic Elements
Created elements by a scientist usually in a labBesides technetium 43 and promethium 61, each synthetic element has more than 92 protons.We call these elements having more than 92 protons Transuranium elementsThese do not belong to metals, nonmetals, or metalloids; they are their own section of the tableAll transuranium elements are synthetic and unstable, and many disintegrate quickly