The Elements - PowerPoint

							The Elements
      Chapter 7
Section 7.1 Prop of s-block
   Objectives:
       Explain how elements in a given group are both
        similar and different

       Discuss the properties of H

       Describe and compare the properties of alkali and
        alkaline earth metals
General Info
   92 naturally occurring elements
   He is the 2nd most common element in
    universe, and is much less on Earth
   O most abundant on Earth
   Atomic # > 92 do not exist in nature
       They’re synthetic
       Created in labs or nuclear reactors
Representative elements
   1A  8A
   s and p orbital
   Diagonal relationships
       Have common characteristics with elements
        diagonal to them
Hydrogen
   1A because 1 valence e-
   7A characteristics
   Contains metallic and nonmetallic properties
   Not considered part of any group
Hydrogen history
   1766 Henry Cavendish discovered H
       “Flammable air” b/c burned when ignited in air


   1783 Lavoisier named H
       Greek “hydro”-water, “genes” - to form




                                              Picture source Wikipedia.com
Hydrogen Isotopes
   Protium
       99.985%
       No neutrons
   Deuterium
       0.015%
       1 neutron
   Tritium
       2 neutrons
       Radioactive
       Produced when cosmic rays bombard water in atmosphere
       “heavy water”

                                                Picture source Wikipedia.com
Hydrogen bonding
   Gain e-
       H + H  stable configuration of He


   Lose e-
       H+ ion with no e-
Group 1A: Alkali metals
   Li
   Na
   K
   Rb
   Cs
   Fr
Alkali Metals
   Arabic “al-qili”
       “Ashes of saltwort plant”
   Easily lose valence e-  1+ charge ion
   Soft like cold butter
   Highly reactive
   Lab samples stored in oil to prevent O
    reaction
   Good conductor of heat/electricity
Lithium (Li)
   Lightest alkali metal
   Found in water, soil and rocks       Picture source
                                         http://www.webelements.com/webelem
   Least reactive of alkali metals      ents/elements/text/Li/key.html


   Li & Mg diagonal relationship
   Used in
       batteries – extend life electric cars
       Dehumidifiers – absorbs water
       Li carbonate – strengthens glass, drug bipolar
        disorder
       Alloys – plane parts b/c strong & lightweight
Na & K
   Most abundant
   Na vapor lamps
   Heat exchanger in nuclear reactors
   Humans and vertebrates need in diets
       K+ most common in cells
       Na+ most common in fluid outside cells
       When nerve cell stimulated
           K+ moves outside the cell when Na+ moves into the
            cell

                                           Picture source Wikipedia.com
More Na and K info
   NaCl most common Na compound
   Prevent spoiling
   Preserve food
   KCl – salt substitute
   K compound found in fertilizers for plant
    growth and development
   KNO3 – explosives for fireworks

            Picture source
            http://www.webelements.com/webelements/elements/text
            /Na/key.html
Other Alkali metals
   Rb
       extremely reactive
       40°C mp
       Burst into flames when exposed to air
   Fr
       Most reactive
       Rare radioactive element
Group 2A: Alkaline Earth
metals
   Be
   Mg
   Ca
   Sr
   Ba
   Ra


             All Picture sources from
             http://www.webelements.com/webelements/elements/text/Ra/key.html
Alkaline Earth Metals
   Medieval alchemist classified solids that did not melt
    in their fires as “earths”
   AEM + O2  oxides  form thin oxide coating
   Shiny solids
   Harder than AM
   Less reactive than AM
   Found combined w/ O and other nonmetals
   Lose 2 valence e-  2+ charge
       Ca, Sr, Ba react with water
       Be no react with water
Beryllium (Be)
   Lightest in Group 2A
   Beryl is Be + Al + Si + O
   Al & Be have diagonal relationship
   Used to moderate n0 in nuclear reactors
   Be-Cu tools used in petroleum refineries




                     Picture source from
                     http://www.webelements.com/webelements/elements/text/Be/key.html
Calcium (Ca)
   Essential for humans
       Maintain teeth and bones
   Calcium carbonate
       Limestone, chalk, marble
       Coral reefs
       Antacid tablets
       Toothpaste abrasives
       Emery boards and sand paper
       Limestone used to build Roman aqueduct
   Calcium carbonate decomposes into lime
                          Picture source from
                          http://www.webelements.com/webelements/elements/text/Ca/key.html
Lime
   One of the most important industrial
    compounds
   Manufacturing steel, paper and glass
   Make soil more acidic
   Wastewater treatment plants
   Remove pollutants from smokestacks
   Lime + water + sand = mortar (paste)
Magnesium (Mg)
   Alloys (Mg + Al + Zn) as strong as steel but
    lighter
   Plants  chlorophyll molecules contain Mg 2+
   Humans  muscle function and metabolism
   Hard water is increase in Ca 2+ and Mg 2+
       Interfere with detergent/ soap action
       Clog pipes, water heaters, and steam irons
Other AEM
   Sr 
       fireworks red color
   Ba 
       used in paints and glass
       diagnostic tool for internal medicine
   Ra 
       highly radioactive
       emit α, β, and γ
       Painted hands on watches b/c glows at night
Section 7.2 Prop of p-block
   Objectives:
       Describe and compare properties of p-block
        elements

       Define allotropes and provide examples

       Explain the importance to organisms of selected
        p-block elements
Group 3A: Boron Group
   B – metalloid
   Al – abundant metal
   Ga – rare metal
   In – rare metal
   Tl – rare metal
More Boron Info
   Lose 3 e-  3+ charge

   Tl  1+ charge
       Lose p e- only


   Very metallic like AM

   Ga and In can form 1+ also
Boron (B)
   Chemical properties like Si
   Borosilicate glass
       Withstand extreme temp changes w/o shattering
   Borax
       Large amount comes from CA Mojave Desert
       Cleaning agent
       Fireproof insulation
   Boric Acid
       Disinfectant in eye wash
   Boron Nitride
       Second hardest material
       Super abrasive
       Used in grinding wheels
Aluminum (Al)
   Most abundant metal
   3rd most abundant element of Earth’s crust
   Combined w/ O or Si
   Bauxite requires LOTS of energy
       Al2O3 major compound in bauxite
         Abrasive
         Strengthens ceramics
         Heat-resistant fabrics

   Ruby and sapphires are crystals of Al2O3
       Cr  red
       Fe + Ti  blue
   Alum (Al sulfate)
       Antiperspirants
       Remove suspended particles during water purification
Gallium (Ga)
   Melts in your hand
   Used in some thermometers b/c liquid state in large
    range (30 – 2403 °C)
   Gallium arsenide (Ga + As)  produce electric
    current when absorbs light
       Used in semiconductor chips
       Light-powered calculators
       Solar panels
       10x more efficient than Si based
   Gallium nitride (Ga + N)
       Blue lasers
       Triple DVD storage capacity (3-2 hr movies per DVD)
       Increase speed and resolution of laser printers
       Lower cancer cell detection device cost
Group 4A: Carbon Group
   C – nonmetal
   Si – metalloid
   Ge – metalloid
   Sn – metal
   Pb – metal
Carbon (C)
   Organic chemistry – study of C-based
    compounds
   1828 – 1st C compound synthesized
       Prior believed only living organisms made C
        based compounds
   Minerals- element or inorganic compound
    found in natural as solid crystal
   Ore- material form which a mineral can be
    removed at a reasonable cost
       Cost to extract not > economic value
C Allotropes
   Allotropes – forms of element in same physical state
    (SLG) that have different structure and properties
   Graphite
       Softest known material
       Good lubricant b/c molecules slide
       3 C attached
   Diamond
       Hardest known material
       4 C attached
       3D solid
       Can cut granite and concrete
   Coal
       Shapeless solid
Silicon (Si)
   Second most abundant element on Earth’s crust
    after O
   Used in
       Computer chips
       Solar cells
 Silicon dioxide (SiO2) AKA: silica
Quartz + weathering  white sand + heat and rapid
  cooling  glass
 Si + C silicon carbide
         Major industrial abrasive
       Carborundum – common name
         Used sticks to sharpen tools
Pb & Sn
   Sn  Coat steel cans; now use Al cans
   Bronze  alloy Sn + Cu, Zn (little for hardness)
   Pewter  40% Pb & 60% Sn
   Softer metal

   Pb  ancient skeletal analysis  dangerously high
    levels
       Toxic
       Used in eating utensils
       Pipes for plumbing
       Gasoline additives
       Paint
       Car storage batteries (Pb-acid) p. 675-676
Group 5A: Nitrogen Group
   N – nonmetal
   P – nonmetal
   As – metalloid
   Sb – metalloid
   Bi – metal
Nitrogen group info
   5 valence e-

   Forms 3+/- charge ions
Nitrogen
   Colorless, odorless, relatively unreactive
   78% Earth’s atmosphere
   Proteins and essential organic compounds
   Bacteria and clover roots “fix” N
   Major industrial use
     Ammonia
           Colorless gas with irritating odor
           Cleaning products
           N source for plants
       25% ammonia  nitric acid
           Produced for explosives
           Dyes
           Fertilizers
           Etching design on metal plates
           TNT (trinitrotoluene)
           nitroglycerine
Phosphorus (P)
   Allotropes
     White P – bursts into flames in air
           Must be stored in water
       Red P – less reactive
           Formed from white P heated in absence of air
           Used on matchboxes for striking surface
     Black P – white or red heated under high pressure
   Phosphoric acid  phosphate compound
     Used in processed cheese, laxatives, baking powder
     Flame retardant coating on fabrics
     Grease remover in cleaning products
     Fertilizers have phosphates
           Harmful to environment
               Normal: phosphates broken down by bacteria  nutrients eaten by algae
                 zooplankton eat algae  fish eat zooplankton
               Increase P ions: increase algae pop  keep light from algae below (die) 
                bacteria decay algae use lots of O  other things die  no decay and
                build up of waste occurs  lake changes to pond or marsh
As, Sb, Bi
   Oldest known elements
   As + S  arsenic sulfide  treat illnesses; As toxic
   Sb + S  antimony sulfide  cosmetics to darken
    eyebrows and make eyes appear larger
   Britannia metal – alloy of Sn + Sb; easily shaped
   Pb storage batteries – contain 7% Sb
   Bi active ingredient in Pepto – diarrhea and nausea
    med
   Wood’s metal – alloy of Bi, Pb, Sn, Cd
       Plug automatic sprinkler; melts when heated and activates
        sprinkler (water)
Group 6A: Oxygen Group
   O – nonmetal
   S – nonmetal
   Se – metalloid
   Te – metalloid
   Po – rare metal
Oxygen Group Info
   6 valence e-
   Nonmetals mainly
   Gain 2 e-
   Forms 2 – charge
   Shares 2 e- for stability when bonded
Oxygen (O)
Allotropes
 Ozone (O3)
        Unstable gas with pungent odor
        Decomposes when exposed to UV light or heat
        Produced in auto emissions
            Irritates eyes, harmful to lung cells, and affects plant growth negatively
   O2
        21% Earth’s atmosphere
        Colorless, odorless gas
        Joseph Priestley (1733-1804) discovered O2
            Heated Hg oxide and candle burned more brightly than in air
        Cellular respiration uses O2 to release energy from carbs
        Separate from other gases by distillation
        Canisters store liquid O2
            Airplanes have small, individual O2 for emergencies
   Most abundant element in Earth’s crust
   Combines with every element except He, Ne, Ar
            H2O
            H2O2
            CO
            CO2
Sulfur (S)
   Combined w/ Hg (cinnabar)
   Combined w/ Pb (galena)
   Uncombined underground
   10 allotropes
   SO2
     Preserve fruit
     Antibacterial agent
     Acid rain
   90% make sulfuric acid
     Fertilizers (50%)
     Steel, paper and paint
   H sulfide
     Rotten egg smell
     Ocean vents energy source for bacteria
     Volcanoes
   Silver sulfide  tarnish
Selenium (Se)
   Na selenate – vitamin supplement contain this
       Vitamin E prevent cell damage
       Inhibit cancer cell growth
   Locoweed plant – absorbs too much  toxic
       Animals become ill
   Light  electricity (solar panels)
   Meters to measure light availability (photography)
   Charge Se particles create image (photocopiers)
   Semiconductors (& Te)
Polonium (Po)
   1898 founded by Marie Curie
   Named after Marie’s home country – Poland
   Extremely toxic
   Radioactive
   Rare metal
Group 7A: Halogens
   F – gas
   Cl – gas
   Br – liquid
   I – solid  gas
   At – radioactive with no known uses
Halogen Info
   “salt formers”
   Reactive nonmetal
   Always found combined with other elements
    in nature
   7 valence e-
   Share 1 e- or gain 1 e-
   Forms 1- charge ion
Fluorine (F)
   Most electronegative element on PT
       Greatest ability to attract e-
   Most active of all elements
       Reacts w/ every element except He, Ne, Ar
   Latin “fluere” – to flow
   Fluorite – F + Ca
       Lower mp of other minerals, easier to separate from ore
   F added to toothpaste and water to prevent tooth
    decay
   F + C – non-stick cooking surfaces
   F + U isotopes  gases separate by differences in
    mass (U enrichment)  provides U-235 fuel for
    nuclear reactors
Chlorine (Cl)
   Deadly gas
   Reacts w/ nearly all elements
   1848 cholera epidemic began in London
     25,000 died
     Culprit: raw sewage flowing into Thames R.
     1855 London 1st city to use Cl to disinfect sewage
   Bleaching agents by textile and paper industry
     Remove stains from clothes
   Cl compound blocks pain signals during dental work
   HCl in stomach digests food
     Remove rust from steel (pickling)
   Cl gas
     Produced from oil refineries
         Plastics  PVC (polyvinyl chloride)
             Floor tiles
             Pipes for indoor plumbing
             Garden hoses
Bromine & Iodine
   Ag + Br and Ag + I
       Coat photographic film
   I  body  maintain thyroid gland
       Control growth and metabolic rate
           Goiter  enlarged thyroid gland
               Lack of I
       Seafood excellent source of I
       Iodized salt (KI, NaI, and NaCl)
   Kills bacteria
   Campers  tablets/crystals to disinfect water
Group 8A: Noble Gases
   He
   Ne
   Ar
   Kr
   Xe
   Rn
Noble Gas Info
   Colorless & unreactive
   Last natural elements to be discovered
   Stable 8 valence e- (except He has 2 e-)
   1962 – Neil Bartlett, inorganic chemist
    created Xe & F compound
   No known compounds for He, Ne, Ar
Helium (He)
   Lightest Noble Gas
   First discovered emission spectrum of sun
   Found in natural gas wells
   He + O  deep sea divers to prevent “bends”
    b/c replace N w/ He
   Lighter than air – blimps, balloons, airships
   He (l) – coolant for superconducting magnets
Neon (Ne)
   Light display
       High voltage electricity passes through Ne in gas
        discharge tube  e- excited  e- return to lower
        state  bright orange light released

           Ar – blue

           He – pale yellow
Argon & Krypton
   Ar most abundant NG on Earth

   1% Earth's atmosphere

   High temp welding

   Both prolong life of filaments in incandescent
    light bulbs
Radon (Rn)
   Dangerous when inhaled

   radioactive
7.3 d- and f-block
   Objectives
       Compare the e- configuration of transition and
        inner transition metals

       Describe the properties of transition elements

       Explain why some transition metals from
        compounds with color and some have magnetic
        properties
General Info
   d- block
       transitional metals
       period 4
   f- block
       Inner transition metals
           Period 6
               Lanthanide series
                 Lanthanum
           Period 7
               Actinide series
                 Actinium

   “B” section
Transition Metals
   Electrical conductivity
   Luster
   Malleable w/ other metals
   Little variation in atomic size, electronegativity,
    ionization energy across a period
   Ag best electrical conductor
   Fe & Ti strength used in structural materials
   Physical properties determined by e- configuration
       Hard solids w/ high bp & mp
       More unpaired e- in d levels , the increase in hardness and
        increase in mp and bp
Ion formation
   2+ charge
       Loses 2 s e-
   Unpaired d  3+ charge or higher
   6+ if w/ F or O
   Most have color (p. 198 Fig. 7-22)
   UV light “color” for Ti, Sc, Zn
   Color change indicates ion change (p. 198
    Fig. 7-23)
Magnetism and metals
   Affected by magnetic field
       Moving e- creates magnetic field
   Diamagnetism
       Unaffected by opposite spinning e- or slightly repelled by
        magnetic field
   Paramagnetism
       Unpaired e- in valence orbital attracted to magnetic field
   Ferromagnetism
       Strong attraction of substance to magnetic field
       Ex: Fe, Co, Ni
       Can form permanent magnets b/c all ions are aligned
Sources of TM
   Cu, Ag, Au, Pt, Pd only TM found uncombined
    naturally b/c unreactive
   Metallurgy – applied science studies and designs
    methods of extracting metals and their compounds
    from ores
       High temp
       Solutions
       Electricity
         Purify metal extracted by other 2 means

         Pig iron  purified and mixed w/other elements  steel w/
          3-4% C
       US imports 60 materials “strategic and critical” b/c
        economic and military dependence on these materials
         Pt, Cr, Co, Mn, W
Uses of TM
   Cu  electrical wiring
   Zn protective coting for other metals
   Fe steel
   Alloys  jet engines, drill bits, surgical
    instruments, armor
   Pt, Pd, Ni  control conditions at which a
    reaction will occur when making plastics,
    petroleum and foods
What our body NEEDS!!!
   C, O, H, N, S, P, Na, K, Ca, Mg, Cl –
    essential body needs
   All period 4 TM except Sc and Ti are needed
    in the body
       Fe  hemoglobin  O grabber  cells
       Zn  aid protein digestion, eliminates CO2
       Mn & Cu  cell respiration
       Co  develop red blood cells
       Vitamin and mineral supplements
Inner Transition Metals
   Lanthanide Series

   Actinide Series
Lanthanide Series
   Silvery metals
   High mp
   Found mixed together
   Extremely difficult to separate
       “hard to get at” (Greek) Dysprosium
   Ytterby, Sweden  1st mined Lanth. ores
   Nd & Pr  welder’s goggles absorb high energy
    radiation
   Oxides Y & Eu  tv screens & color computer
    monitors emit bright red light when excited
   Misch metal – 50% Ce  steel industry  remove C
    from Fe & steel
   Movie projectors, high-intensity searchlights, lasers,
    tinted sunglasses
Actinide Series
   Radioactive
   3 exist in nature (Th, Pa, U)
   Rest are synthetic
       Transuranium elements
           92 +
           Created in particle accelerator or nuclear reactor
           Quickly decay
           Pu-239 exception (thousands of yrs)
               Fuel nuclear power plants

   Am  smoke detectors
Credits
   Non-cited pictures are from Microsoft Clip Art