Elements and Periodic Table

1. Elements and Periodic Table Bonding, Compounds, Periodic Table

2. What does the periodic table tell me? • Element symbol • Atomic number: number of protons (and usually electrons, neutrons) • Atomic mass: the average of all the isotopes’ mass • What type of element it is (metal, nonmetal, etc) • What elements can bond together (valence #) • In what ratio elements bond (oxidation #)

3. Element symbol Atomic mass Atomic number Reading the Periodic Table: Elements S 16 32.06

4. Types of Elements • Metals: usually shiny, conductors, malleable, ductile, solids at room temperature. On left side of periodic table • Non-metals: gas or brittle solid at room temperature, insulators. On right side of periodic table. • Metalloids: have properties of both metals and non-metals. Between metals and non-metals.

5. Three types of Elements

6. Things to remember with symbols • They are either one or two letters. • Only the first letter is capitalized! • Some symbols are based on the Latin name • Some of the newest symbols use three letters until they are renamed (the atomic number in Latin)

7. Element symbols you need to know Gold Au Chlorine Cl Silver Ag Sodium Na Iron Fe Hydrogen H Lead Pb Helium He Copper Cu Carbon C

8. More element symbols Potassium K Neon Ne Mercury Hg Zinc Zn Iodine I Titanium Ti Oxygen O Aluminum Al Ca Calcium Sulfur S

9. Atomic Masses • The mass comes from: • the average mass of the isotopes • protons and neutrons each weigh one atomic unit • Remember Isotopes - different number of neutrons. • Identified by name and mass number. • Boron-10, Boron-11 • Try It! 5 atoms of Boron, four are Boron-10, one is Boron-11. What is the average atomic mass? (10 + 10 + 10 + 10 + 11) / 5 = 10.2 u

10. What’s the diff? • Atomic Weight: Is an AVERAGE – usually in decimal form. On the periodic table • Mass number: The weight of that specific atom. Is a whole number. Often listed in the name (Boron-10, Carbon-14, Uranium-235) • We will be more concerned with mass number because it is how we find the number of neutrons! (mass number-atomic number = neutron number)

11. Periodic Table Non-metals Noble Gas Metalloids Halogen Metals Transition Metals

12. Types of Elements • Noble Gas: Chemically stable. Has outer valence level full. “Happy” AKA: Inert elements. Don’t bond with others. • Halogens: Are non-metals. Bond VERY easily. Have 7 electrons in outer shell. • Non-metals: Do not easily conduct electricity or heat. • Metalloids: Have traits of both metals and non-metals. • Metals: Good conductor of heat and electricity, shiny, ductile (pulled into a wire), and malleable (pounded into flat sheets) • Transition metals: Metals that can have two different valence numbers. Is shown in the formula. Example: Fe (II)

13. Alkali metals Periodic Table Alkaline Earth metals Transition metals

14. Hindenburg (5 minutes)

15. Reasons for the crash (7 minutes)

16. Element symbols you need to know Gold Au Chlorine Cl Silver Ag Sodium Na Iron Fe Hydrogen H Lead Pb Helium He Copper Cu Carbon C

17. More element symbols Potassium K Neon Ne Mercury Hg Zinc Zn Iodine I Titanium Ti Oxygen O Aluminum Al Ca Calcium Sulfur S

18. Periodic Table Video Clip1

19. Periodic Table video clip2

20. Word Wizard vocabulary

21. Word wizard: Ionic Bond Your definition Important Points Ionic Bond Bond that is formed by the “stealing” of electrons. One atom is now + and one is now -. This makes them attract to each other. Most are solid at room temp. Examples Non-Examples Sodium Chloride: NaCl Sugar: C6H12O6 Water: H2O Diatomic molecules: Cl2, H2, N2 (gasses)

22. Word wizard: Covalent Bond Your definition Important Points Bond that is formed by the “sharing” of electrons. A stronger bond than ionic. Atoms can share more than one electron. Most are liquid or gas at room temp. Covalent Bond Examples Non-Examples Water: H2O Diatomic molecules: Cl2, H2, N2 (gasses) Sodium Chloride: NaCl Sugar: C6H12O6

23. Word wizard: Polar Molecule Your definition Important Points A molecule that has a positive end and a negative end Polar will mix with polar. Polar will not mix with non-polar Polar Molecule Examples Non-Examples Water: H2O Sugar: C6H12O6 Salt: NaCl Oil Grease Gasoline

24. Word wizard: Non-Polar Molecule Your definition Important Points Non-polar will mix with non-polar. Non-polar will not mix with polar A molecule that has an equal charge all over. Non-polar Molecule Examples Non-Examples Cooking Oil Grease Car oil (things that don’t mix with water) Water: H2O Sugar: C6H12O6 Salt: NaCl

25. Word wizard: Anion Your definition Important Points Anions have more electrons than protons. This makes them negative overall. An ion that has a negative charge; has extra electrons. anion Examples Non-Examples Chlorine Oxygen Nitrogen Non-metals Sodium Potassium Magnesium Metals

26. Word wizard: Cation Your definition Important Points Cations lose electrons. They have more protons than electrons and are positively charged. An ion that is positively charged; has less electrons Cation Examples Non-Examples Sodium Potassium Magnesium Metals Chlorine Oxygen Nitrogen Non-metals

27. Word wizard: Chemical Formula Your definition Important Points Large and small letters. Shows what elements are in a compound and how many of each. A shorthand way of writing compounds using their symbols. Chemical formula Examples Non-Examples Water Sugar Salt H2O C6H12O6 NaCl

28. Word wizard: Chemically Stable Your defintion Important Points Elements that have the outer electron shell full. Also called “Noble Gases” or “Inert Elements” Will not typically bond with other elements. Likes to be ALONE! Chemically Stable Examples Non-Examples Helium Krypton Neon Xenon Argon Radon Gold Carbon Sodium Nickel Potassium Oxygen

29. Valence Numbers Valence 1 2 3 4 5 6 7 8

30. Diatomic Molecules • Covalent bond between identical atoms. • Usually a gas • Examples: • H2 (hydrogen gas) • O2(oxygen gas) • N2(nitrogen gas) • Nitrogen has 5 electrons in the outer shell. • It wants 8. • Two nitrogen atoms share three electrons. • BONDED!

31. Making Compounds Let’s bond, shall we?

32. Valence Numbers • Valence electrons: how many electrons are in the outer shell. • Chemically stable: elements having their outer shell full. The noble gases are chemically stable without bonding. • To fill the outer shell, elements can share or steal electrons (bond). • To be “Happy” atoms typically want 8 electrons in the outer shell (ionic or covalent bonds)

33. Ionic bonding • Stealing electrons • This makes one negatively charged (it has an extra electron that it stole). The other is now positively charged (had an electron taken). Opposites attract! • Ionic bonds are weaker than covalent. • Compounds that are solids at room temperature are usually from ionic bonds.

34. Covalent Bonding • From sharing electrons • Covalent bonds are stronger than ionic • Compounds that are liquids or gas at room temperature are typically covalent bonds. • Diatomic: Some elements will covalently bond with themselves!

35. Common Household Compounds NaHC03 Baking Soda: Carbon Monoxide: CO SiO2 Sand: Ammonia: NH4 Carbon Dioxide: CO2 Salt: NaCl Bleach: NaClO Propane: C3H8 Vinegar: HCH3O2 Stomach Acid: Water: H2O HCl

36. Dihydrogen Monoxide • The dangers, uses and potential threats posed by this chemical, Dihydrogen Monoxide, are widespread, and some feel, terrifying. Here is just a small taste of what Dihydrogen Monoxide (DHMO) is: • Some call Dihydrogen Monoxide the "Invisible Killer" • In it’s gaseous form, DHMO can cause severe burns • Dihydrogen Monoxide is found in all cancerous tumors • Dihydrogen monoxide was found at every recent school shooting • Athletes use DIHYDROGEN MONOXIDE, or DHMO, to enhance performance • Dihydrogen Monoxide has been found to cause failure in automotive breaks • Dihydrogen Monoxide is a major component of acid rain • Thousands die each year after inhaling dihydrogen monoxide • Dihydrogen Monoxide can be deadly • Visit DHMO.org to find out more

37. What’s in a name? • Examples: • Carbon Monoxide CO • Carbon Dioxide CO2 • Dihydrogen Monoxide ?? • Mono = one • Di = two • Tri = three • Tetra = four • Penta = five H2O

38. Dot Diagrams • What you need to know to make a dot diagram: • Chemical symbol • valence number • How to draw the dot diagram of an element: 1. Write the symbol 2. Find the valence number 3. Fill in dots • two together (the S ones) • one in other sides until you run out of room. P

39. More Dot Diagrams F Li Ge Mg Se Kr

40. I’m still seeing dots! Sr As Why is this one right? He Because Helium only has two electrons in the first place!

41. Oxidation numbers +1 +3 +/-4 -2 -1 +2 -3

42. Making Compounds • Criss-Cross Method: • List the Metal first, non-metal second. • Write the oxidation number above the symbol. • Criss-cross the numbers. (a 1 does not need to be written, drop the + or -) • Final answer lists only the subscripts (numbers below the line) • If they are the same number, they cancel out Example: Combine Hydrogen and Chlorine +1 -1 H Cl = HCl

43. Now try these... Hydrogen and Oxygen +1 -2 H O H2O Magnesium and Nitrogen -3 +2 Mg N Mg3N2

44. Remember the “criss cross” method. Use the oxidation number Don’t write in 1’s or the charges Oxidation numbers of transition elements are given in a roman numeral. Put in “lowest terms” Writing Equations (again??) Example: Combine H and O +1 -2 H O H2O Example: Combine Fe (III) and O +3 -2 Fe O Fe2O3

45. Monoatomic Ions: “normal” one element can get from the periodic table or roman numerals what you’ve been working with Example: H20 Polyatomic Ions: compounds that always work together. Always has more than one element Get the information off a chart Criss cross method still works. Keep these elements together! Writing Equations: something new Example: Combine Potassium and Permanganate +1 -1 K MnO4 KMnO4

46. More Practice: Polyatomic Ions Combine: Iron (II) and Nitrate +2 -1 Fe NO3 Fe(NO3)2 Combine: Calcium and Carbonate -2 +2 Ca CO3 CaCO3

47. Your definition Important Points Alloy Real example Analogy/memory hook Word wizard The mixture can have new properties. (lower melt point, stronger, etc. Two or more metals melted down and mixed together. Not ALL metals are mixtures. (All = alloy) Alloys are like allies (mixed but not the same) Sterling silver, 14 karat gold, bronze, brass

48. Your definition Basic equation A + B AB Synthesis Reaction Real example Analogy/memory hook 2Mg + O2 2MgO Word wizard Reaction where substances are combined to make a new substance. Like two people going out and becoming a “couple”. Dating is a “sin”

49. Your definition Basic equation A + BC AC + B D + BC BD + C Single replacement Reaction Real example Analogy/memory hook Li + FeBr2 LiBr + Fe Word wizard One ingredient “kicks out” the other. Leaders always stay leaders! Getting “dumped” for someone else. One ends up single

50. Your definition Basic equation AB + CD AD + CB Double replacement Reaction Real example AgNO3 + NaCl AgCl + NaNO3 Analogy/memory hook Word wizard Elements will change partners in this type of reaction. Leaders are always leaders! Switching dates at the prom. Nobody gets left alone!