Post on 22-Dec-2015
32. Valence electrons and atomic numbers.
• Atomic numbers increase as you move across the periodic table
• Number of valence electrons also increase
• Transition elements are exception
33. What are the subatomic particles for an isotope.
• Ex. Carbon-12 & Carbon-14• 6 protons for each• Carbon-12– Neutrons = 6
• Carbon-14– Neutrons = 8
34. Oxidation Number
• Electrons lost or gained• See periodic table• Metals (positive) & nonmetals
(negative)
35. Fission and Fusion• Fission: when 2 nuclei separate(chain
reaction)• Fusion: when 2 nuclei come together– Ex. Sun
• Both take small masses and convert into great amounts of energy
36. Uses of nuclear applications
• Medical–Radioactive tracers –Radiation for cancer treatment
• Nuclear power plants• Nuclear weapons
37. Molecule and Atom
• Molecule: covalently bonded group of elements–Smallest part of a compound
• Atom : smallest piece of matter
38. Types of Chemical Bonds
• Ionic: metal + nonmetal• Covalent: nonmetal + nonmetal–Single, double, or triple bonds–Polyatomic ions
39. Chemical bonding and stability
• To complete outer energy level• * remember * 8 valence electrons• Exception: Hydrogen and Helium
Argon Atom
40. How does covalent bonding cause stability?
• Ex. Group 14: 4 valence electrons–Would take too much energy to lose
or gain 4 electrons –More chemically stable to just share
42. Ionic & Covalent Bonding
• Ionic Bonds (crystalline)–Metal + Nonmetal–Ex. NaF, MgO, Al2O3
• Covalent Bonds (molecular)–Nonmetal + nonmetal–*Prefixes*–Ex. P3N5 , PCl3
43. Writing chemical formulas for Binary Ionic Compounds
• Write name of positive ion first, then add –ide to end of negative ion
• Ex. KCl–Potassium Chloride
• Ex. BaF2
–Barium Fluoride
44. Balanced chemical equation
• Balance using only coefficients• Same number of atoms of each element
on each side2Mg(s) + O2 (g) 2Mgo(s)
46. Endothermic and Exothermic Reactions
• Endothermic: energy is used, temperature decreases– Ex. Cold pack
• Exothermic: energy released, temp. increases– Fire
47. Evidence of Chemical Reaction
• Evolution of gas• Precipitate formation • Changes in :–Temperature–Color–Smell
50. Single and Double Displacement Reaction
• Single DisplacementA + BC AC + BFe + CuSO4 FeSO4 + Cu
• Double DisplacementAB + CD AD + CBBa(NO3)2 + K2SO4 BaSO4 + 2KNO3
51. Reaction Rates• Affected by:–Temperature–Surface area–Add a catalyst (does not change
amount of product)
• Buoyancy (Archimede’s Principle)
• Bernoulli’s Principle• Pascal’s Principle• Heterogeneous
Mixture• Homogeneous
Mixture
• Kinetic Theory• Charles’s law• Boyle’s Law