Basic Chemistry:

1. Basic Chemistry: Elements & Atoms

2. I. Elements & Atoms Element • _________ = A substance that cannot be broken down into simpler substances. • Periodic Table • 1-92 occur in _______ (natural elements) • 93 and above are ___________ (man-made) nature synthetic

4. Trace Elements: Found in very _______ amounts but are _________ to proper activities. Ex. Iron, magnesium, iodine 25 • Natural Elements: • ____ are essential to living things. • Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N) make up 96% of human mass. small essential

5. ATOM • _______ = Smallest particle of an element that has the characteristics of that element.

6. 3 Subatomic particles make up an atom: positively Protons • 1. _______ (p+) = ________ charged particles • 2. ________ (n) = no charge (_______) Neutrons neutral

7. 3 Subatomic particles make up an atom: negative Electrons • 3. ________ (e-) = (________ charge) move nearly at the speed of light ; form a cloud around the nucleus

8. 2 parts of an atom: Nucleus • ________ = center of atom; contains ________ & _________. • ______________________________ = around the nucleus protons neutrons Electron cloud/energy levels

9. electrons protons zero • Atoms contain an equal number of ________ and ___________ so the overall charge of an atom is ______.

10. II. Isotopes: Isotopes • __________ = Atoms of the same element that have different numbers of ________ neutrons

11. II. Isotopes: atomic mass numbers • Named by their ____________________ • C-12 = _____ + 6p+ • C-13 = _____ + 6p+ • C-14 = _____ + 6p+→ radioactive 6n 7n 8n

12. III. Atomic Number & Atomic Mass protons Atomic Number electrons • ______________ = number of _______ and/or _________ of an atom. • Ex. Na-23 contains 11 electrons and 11 protons • ______________ = the _____ of protons and neutrons in an atom. • ___________________________________ Mass Number sum # of protons (p+) + # of neutrons (n)

13. IV. Energy Levels & Diagramming Atoms: Energy Levels • _______________ = regions around the _________ that electrons travel. • 1st energy level can ONLY have 2 electrons (except Hydrogen, it has only 1 e-) nucleus

14. IV. Energy Levels & Diagramming Atoms: Octet Rule • ____________ = each energy level AFTER the first can have up to ___ electrons. • The 3rd energy level has 18 e- 8

15. What atom is represented in this picture? • ___________ • How do you know? • ___________________________________ 8 Sodium (Na) Sodium’s atomic number is 11 so it has 11 e-.

16. Example: Helium (He) • Atomic # = 2; Mass # = 3 2e- 2p+ 1n nucleus

17. Example: Chlorine (Cl) • Atomic # = 17; Mass # = 35 7e- 2e- 8e- 17p+ 18n

18. Example: Carbon (C) • Atomic # = 6; Mass # = 14 2e- 4e- 6p+ 8n

19. Basic Chemistry: Interactions of Matter

20. I. Compounds and Bonding: Compound • __________ = a substance made of chemically combined elements. • Atoms bond to form __________________ • Atoms need _____ in OUTER energy level to be stable; Exception: hydrogen & helium need 2e- Open bonding sites (electrons) encourage _________. stable compounds 8 e- bonding

21. I. Compounds and Bonding: • Elements can combine in two ways” • __________________: Covalent bonds ________ electrons The positively charged nucleus is ___________ to the negatively charged electrons. Water, sugars, fats and proteins are ____________________ Covalent Bonding SHARE attracted covalent molecules

22. Covalent Bond: occurs between nonmetals

23. Examples of Covalent Bonding

24. Van der Waals Forces:

25. I. Compounds and Bonding: Molecule • __________ = a group of covalently bonded atoms with ___ charge. • Ex: H2O 2 hydrogen atoms + 1 oxygen atom • Oxygen needs _____ electrons to become stable • Each hydrogen needs ____ electron to fill orbital • Therefore, they ________!! no two one SHARE

26. I. Compounds and Bonding: Ionic Bonding • _______________: __________ of electrons creating ions that attract each other = ____________ TRANSFER Ionic Bond

27. I. Compounds and Bonding: Ions • ______ = charged atoms because they have ________ or ______ electron(s) • Atoms that ______ electrons become more _________ • Atoms that ______ electrons become more _________ • Atoms gain/lose electrons efficiently gained lost lose positive gain negative

29. Ionic Bond: occurs between metals and nonmetals

30. Ions in living things: sodium • Include - ________, potassium, calcium, chloride, carbonate ions. • Help maintain _____________ as these ions travel in and out of cells. • Help transmit _________ among cells that allow you to see, taste, hear, feel and smell. homeostasis signals

32. I. Compounds and Bonding: GAIN • More effective to ______ an electron than to ______ an electron!! LOSE

33. II. Water is Polar: Polar • _______ = unequal distribution of charge • Each molecule has a __________ end and a __________ end. positive negative

34. II. Water is Polar: • Ex: Water (H2O) molecule  Oxygen is much stronger and therefore has a stronger ________________ than the hydrogen’s positive charge. negative charge

35. II. Water is Polar: • Because of water’s polarity, it can __________ many ionic compounds and other polar compounds such as ________. dissolve sugars

36. II. Water is Polar: adhere • The water molecules also ________ to each other because of __________ (unequal distribution of charge) • The attraction of opposite charges forms a ______ bond called a _______________. • This keeps large molecules __________! • (Ex: proteins) polarity weak hydrogen bond together

37. III. Uniqueness of Water – due to its polarity Cohesion • _________ = the attraction between like molecules • _________________ results from the cohesive properties of water. • The polarity of water causes the surface layer of water molecules to act like a stretched film over the surface of the water (______________) Ex. Water striders Surface tension surface tension

38. III. Uniqueness of Water – due to its polarity • 2. Creeps up in thin tubes • ________________ • The polarity of water allows _______ to get water from the ________. • Water creeps up tubes in plant roots and stems. (capillary action) plants ground

39. III. Uniqueness of Water – due to its polarity Expands when it freezes • _________________________ • Ice is _____ dense than water (ice floats) less

40. Water is Less Dense as a Solid • Which is ice and which is water?

41. Water is Less Dense as a Solid Water Ice

42. Basic Chemistry: Chemical Reactions

43. Examples of chemical reactions

44. I. Chemical Reactions: • All the chemical reactions in our bodies are called ____________. • Breakdown and reassemble molecules in the body. ________________ are broken and formed during chemical reactions. metabolism Chemical Bonds

45. II. Writing a Chemical Equation:

46. II. Writing a Chemical Equation: • ______________ = # of molecules of a compound • Ex: 6O2 = 6 molecules of Oxygen (O) • 3H2O = ___ molecules of H2O CH4 + 2O2 CO2 + 2H2O Coefficient 3

47. II. Writing a Chemical Equation: • _________ = # of atoms of an element • Ex: CH4 = 1 atom C, 4 atoms H • CO2 = ___ atom of C, ___ atoms of O CH4 + 2O2 CO2 + 2H2O Subscript 1 2

48. II. Writing a Chemical Equation: • How many atoms of O are in 6O2? ____ atoms of O! 12

49. III. Balancing Chemical Equations: same • In ALL chemical equations the ______ number of atoms of elements are on the reactant and product side of chemical equations. • Why? • Because the _________________________ _____________ (atoms are never created or destroyed; they are simply rearranged) Law of Conservation of Matter

50. III. Balancing Chemical Equations: • We balance equations so the Law of Conservation of Matter is NOT __________! • We must always balance equations using ____________!! violated coefficients