1. Regents Review Matter Atomic Structure Atomic Theories Electron Energy Level Transitions Radiation Half Life Fission/Fusion Periodic Table Arrangement Periodic Trends Bonding Formula Writing Molecular Polarity Intermolecular Forces Naming Moles Percent Comp/Emp Formula Balancing Reactions Reaction Types Stoichiometry MORE

2. More Phases Heat Equations Heating Curves Gas Laws Solutions/Solubility Molarity/Concentration Acids & Bases Neutralization/Titration Reaction Rates Equilibrium LeChatelier’s Principle Potential Energy Diagrams Reduction – Oxidation Electrochemical Cells Hydrocarbons Functional Groups Organic Reactions BACK

3. Matter • Anything that has mass and volume • Classified into 2 categories • Pure Substance • Sometimes just referred to as substances • Mixtures

4. Matter

5. Pure Substances • Element • simplest form of matter that has a unique set of properties. • Can’t be broken down by chemical means • Compounds • substance of two or more elements chemically combined in a fixed proportion • Can be broken down by chemical means

6. Mixtures • Physical blend of two or more substances • Two Types: • Homogeneous • Composition is uniform throughout • Heterogeneous • Composition is not uniform throughout

7. Separating Mixtures • Mixtures can be separated based on their physical properties • Boiling Pt, Freezing Pt, Density, Molecular Polarity, Particle Size • Process Examples • Filtering, Distillation, Evaporation, Crystallization, Chromatography, Desalination, Extraction

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9. Atom • Atoms are made of subatomic particles • Protons • Neutrons • Electrons

10. Electron • Discovered first • Negative charge (-1) • Approx mass ~ 0u • Found outside of nucleus • Valence Electron • Electrons in the outermost energy level

11. Proton • Discovered second • Positive charge (+1) • Approx mass ~ 1u • Found inside nucleus

12. Neutron • Discovered last • No charge (0) • Approx mass ~ 1 atomic mass unit (u) • Just slightly larger than a proton • Found inside nucleus

13. Atomic Structure • Atoms have no net charge • # of electrons = # of protons • Nucleus • Center of atom, contains protons and neutrons • Positive charge

14. Atomic Structure • Atomic Number • Number of protons • All atoms of the same element have the same number of protons • Mass Number • Number of protons and neutrons in an atom • # of Neutrons = Mass Number – Atomic Number

15. Atomic Structure • Isotope • atoms of the same element with different number of neutrons • Ion • Atom or group of atoms that have gained or lost one or more electrons • Have a charge

16. Average Atomic Mass • Atomic Mass • Weighted average based on the relative abundance and mass number for all naturally occurring isotopes • Relative Abundance • Percent of each naturally occurring isotope found in nature

17. Atomic Mass Example • C-12 98.9% • C-13 1.1% • Carbon = 0.989*12 + 0.011*13 = 12.011u

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19. Atomic Theories • Dalton’s Atomic Model • Also called Hard Sphere Model • First model • Plum Pudding Model • Uniform positive sphere with negatively charged electrons embedded within. • Came as a result of discovery of electron

20. Rutherford Gold Foil Experiment • Shot alpha particles at gold foil • Most went through, some were deflected back • Conclusions • Atom is Mostly Empty Space • Dense positive core (nucleus)

21. Atomic Theories • Rutherford Model • Dense positive core (nucleus) • Electrons moving randomly around nucleus • Bohr Model • Dense positive core (nucleus) • Electrons in specified circular paths, called energy levels

22. Atomic Theories • Wave Mechanical Model • Dense positive core (nucleus) • Electrons in orbitals • Regions of space where there is a high probability of finding an electron • Modern (current) Model • AKA Quantum Mechanical Model, Electron Cloud Model

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24. Energy Level Transitions • Electrons can move between energy levels • Gaining energy will move an electron outward to a higher energy level • When an electron falls inward to a lower energy level, it releases a certain amount of energy as light

25. Energy Level Transitions • Energy released forms emission spectra

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27. Radiation • Three Types • Alpha • Beta • Gamma

28. Radiation • Three Types

29. Symbols Alpha Beta Gamma

30. Transmutations • Any reaction where one element is transformed into a different element • Nuclear Reactions • Natural • Has one reactant • Alpha and Beta Decay • Artificial • Has more than one reactant • Particle Accelerators

31. Radioactive Decay • Radioisotopes will undergo decay reactions to become more stable • Alpha Decay • Beta Decay

32. Radioisotopes • You must know these radioisotopes and uses • I-131 - Diagnosing and treating thyroid disorders • Co-60 - Treating cancer • C-14 - Dating once-living organisms • Compared to C-12 • U-238 - Dating geologic formations • Compared to Pb-206

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34. Half Life • Amount of time for half of a sample to decay into a new element • Table N

35. Half Life Equations Mass Left = Fraction Remaining Original Mass t = total amount of time elapsed T = half-life

36. Example • How many half lives does it take for a sample of C-14 to be 11430 yrs old?

37. Example • What fraction of P-32 is left after 42.84days?

38. Example • How long will a sample of Rn-222 take to decay down to 1/4 of the original sample? 7.646d

39. Practice • How much Carbon-14 was originally in a sample that contains 4g of C-14 and is 17145 years old? 32g

40. More Practice • How much 226Ra will be left in a sample that is 4797 years old, if it initially contained 408g? 51g

41. And One More…. • What is the half life of a sample that started with 144g and has only 9g left after 28days? 7d

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43. Fission • Splitting of a larger atom into two or more smaller pieces • Nuclear Power Plants • One Example:

44. Fusion • Joining of two or more smaller pieces to make a larger piece • Sun, Stars • Examples

45. Energy Production • Energy is produced by a small amount of mass being converted to energy • This happens in both fission and fusion • More energy is produced by fusion than any other source • E=mc2

46. Fission vs. Fusion • Advantages of Fission • Produces a lot of energy • Disadvantages of Fission • Exposure to radiation • Produces material with long half life

47. Fission vs. Fusion • Advantages of Fusion • Produces more energy than fission • Disadvantages of Fusion • Have not been able to sustain stable reaction for energy production

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49. Periodic Table • Arranged in order of increasing atomic number • Columns are called Groups • Numbered 1-18 • Rows are called Periods

50. Group Names • Group 1 - Alkali Metals • Group 2 - Alkaline earth metals • Group 17 – Halogens • Group 18 - Inert or Noble gases • Groups 3-11 – Transition Metals • Bottom 2 rows – Inner Transition