1. 1 The Elements Chapter 7 Friendly caution: There are 66 slides, so print CAREFULLY

2. 2 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

3. 3 General Info 92 naturally occurring elements He is the 2 nd 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

4. 4 Representative elements 1A  8A s and p orbital Diagonal relationships Have common characteristics with elements diagonal to them

5. 5 Hydrogen 1A because 1 valence e- 7A characteristics Contains metallic and nonmetallic properties Not considered part of any group

6. 6 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

7. 7 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

8. 8 Hydrogen bonding Gain e- H + H  stable configuration of He Lose e- H+ ion with no e-

9. 9 Group 1A: Alkali metals Li Na K Rb Cs Fr

10. 10 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

11. 11 Lithium (Li) Lightest alkali metal Found in water, soil and rocks Least reactive of alkali metals 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 Picture source http://www.webelements.com/webelem ents/elements/text/Li/key.html

12. 12 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

13. 13 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 KNO 3 – explosives for fireworks Picture source http://www.webelements.com/webelements/elements/text /Na/key.html

14. 14 Other Alkali metals Rb extremely reactive 40°C mp Burst into flames when exposed to air Fr Most reactive Rare radioactive element

15. 15 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

16. 16 Alkaline Earth Metals Medieval alchemist classified solids that did not melt in their fires as “earths” AEM + O 2  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

17. 17 Beryllium (Be) Lightest in Group 2A Beryl is Be + Al + Si + O Al & Be have diagonal relationship Used to moderate n 0 in nuclear reactors Be-Cu tools used in petroleum refineries Picture source from http://www.webelements.com/webelements/elements/text/Be/key.html

18. 18 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

19. 19 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)

20. 20 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

21. 21 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

22. 22 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

23. 23 Group 3A: Boron Group B – metalloid Al – abundant metal Ga – rare metal In – rare metal Tl – rare metal

24. 24 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

25. 25 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

26. 26 Aluminum (Al) Most abundant metal 3 rd most abundant element of Earth’s crust Combined w/ O or Si Bauxite requires LOTS of energy Al 2 O 3 major compound in bauxite Abrasive Strengthens ceramics Heat-resistant fabrics Ruby and sapphires are crystals of Al 2 O 3 Cr  red Fe + Ti  blue Alum (Al sulfate) Antiperspirants Remove suspended particles during water purification

27. 27 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

28. 28 Group 4A: Carbon Group C – nonmetal Si – metalloid Ge – metalloid Sn – metal Pb – metal

29. 29 Carbon (C) Organic chemistry – study of C-based compounds 1828 – 1 st 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

30. 30 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

31. 31 Silicon (Si) Second most abundant element on Earth’s crust after O Used in Computer chips Solar cells Silicon dioxide (SiO 2 ) 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

32. 32 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

33. 33 Group 5A: Nitrogen Group N – nonmetal P – nonmetal As – metalloid Sb – metalloid Bi – metal

34. 34 Nitrogen group info 5 valence e- Forms 3+/- charge ions

35. 35 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

36. 36 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

37. 37 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)

38. 38 Group 6A: Oxygen Group O – nonmetal S – nonmetal Se – metalloid Te – metalloid Po – rare metal

39. 39 Oxygen Group Info 6 valence e- Nonmetals mainly Gain 2 e- Forms 2 – charge Shares 2 e- for stability when bonded

40. 40 Oxygen (O) Allotropes Ozone (O 3 ) 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 O 2 21% Earth’s atmosphere Colorless, odorless gas Joseph Priestley (1733-1804) discovered O 2 Heated Hg oxide and candle burned more brightly than in air Cellular respiration uses O 2 to release energy from carbs Separate from other gases by distillation Canisters store liquid O 2 Airplanes have small, individual O 2 for emergencies Most abundant element in Earth’s crust Combines with every element except He, Ne, Ar H 2 O H 2 O 2 CO CO 2

41. 41 Sulfur (S) Combined w/ Hg (cinnabar) Combined w/ Pb (galena) Uncombined underground 10 allotropes SO 2 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

42. 42 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)

43. 43 Polonium (Po) 1898 founded by Marie Curie Named after Marie’s home country – Poland Extremely toxic Radioactive Rare metal

44. 44 Group 7A: Halogens F – gas Cl – gas Br – liquid I – solid  gas At – radioactive with no known uses

45. 45 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

46. 46 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

47. 47 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 1 st 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

48. 48 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

49. 49 Group 8A: Noble Gases He Ne Ar Kr Xe Rn

50. 50 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

51. 51 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

52. 52 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

53. 53 Argon & Krypton Ar most abundant NG on Earth 1% Earth's atmosphere High temp welding Both prolong life of filaments in incandescent light bulbs

54. 54 Radon (Rn) Dangerous when inhaled radioactive

55. 55 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

56. 56 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

57. 57 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

58. 58 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)

59. 59 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

60. 60 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

61. 61 Uses of TM Cu  electrical wiring Zn  protective coating 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

62. 62 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

63. 63 Inner Transition Metals Lanthanide Series Actinide Series

64. 64 Lanthanide Series Silvery metals High mp Found mixed together Extremely difficult to separate “hard to get at” (Greek) Dysprosium Ytterby, Sweden  1 st 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

65. 65 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

66. 66 Credits Non-cited pictures are from Microsoft Clip Art Information from Glencoe Chemistry Matters, TX edition Arranged and organized by Michelle Estrada