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FTCE Chemistry SAE Preparation Course. Session 2. Lisa Baig Instructor. Session Norms. Respect No side bars Work on assigned materials only Keep phones on vibrate If a call must be taken, please leave the room to do so. Course Outline. Session 1 Review Pre Test Competencies 6, 7 and 8
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FTCE Chemistry SAEPreparation Course Session 2 Lisa Baig Instructor
Session Norms • Respect • No side bars • Work on assigned materials only • Keep phones on vibrate • If a call must be taken, please leave the room to do so
Course Outline Session 1 Review Pre Test Competencies 6, 7 and 8 Competencies 1 & 2 Competency 5 Session 2 Competency 3 Competency 4 Post Test
Required Materials • Scientific Calculator • 5 Steps to a 5: AP Chemistry • Langley, Richard, & Moore, John. (2010). 5 steps to a 5: AP chemistry, 2010-2011 edition. New York, NY: McGraw Hill Professional. • Paper for notes • State Study Guide
Chemistry Competencies • Knowledge of the nature of matter (11%) • Knowledge of energy and its interaction with matter (14%) • Knowledge of bonding and molecular structure (20%) • Knowledge of chemical reactions and stoichiometry (24%) • Knowledge of atomic theory and structure (9%) • Knowledge of the nature of science (13%) • Knowledge of measurement (5%) • Knowledge of appropriate laboratory use and procedure (4%)
Electronegativity • Fluorine is the most electronegative element. • Pattern of increasing electronegativity moves from bottom to top, and from left to right across the periodic table.
Chemical Bond Mutual electrical attraction between the nuclei and valence electrons of different atoms that bind the atoms together Atoms would like to have 8 Valence electrons. These bonds help the atoms to achieve their full valence shells Three Types Ionic Covalent Metallic
Force of attraction between oppositely charged ions Occurs between Metal and Non-Metal elements The Non-metal “steals” the valence electron(s) from the Metal Forms a crystalline structure of these positive and negative charges Typically solids at room temperature Ionic Bond
Ionic Character • Ionic Bonds are bonds with > 50% ionic character • Difference in Electronegativity of involved atoms is >1.7
Covalent Bond • Sharing of valence electron pairs by 2 atoms • Occurs between 2 Non-metal elements • Or the SAME non-metal element • Can share one, two or three pairs of electrons • Single Bond = 1 pair (1 sigma) • Double Bond = 2 pairs (1 sigma, 1 pi) • Triple Bond = 3 pairs (1 sigma, 2 pi) • Sharing can also be “unequal” • Called a POLAR covalent bond • Typically liquids or gases at room temperature
Character • Ionic Character: • Polar Covalent Bonds have between 5% and 50% ionic Character • Non-Polar Covalent Bonds have less than 5% ionic character • Difference in Electronegativities • Polar Covalent Bonds have between 0.3 and 1.7 as a difference in electronegativities • Non-Polar Covalent bonds have less than 0.3 difference in electronegativities
Break Time Take a 10 minute break
Ionic Compounds • Ion names are used in combination • Cation- same as the element • Transitional Metals use Roman Numerals to represent Charge • Anion- replace the ending syllable of the element name with –ide • Polyatomic Ions- use the name of that ion- do not try to rename. Use “criss-cross” to determine charges
CuCl2 Copper (II) Chloride CuO Copper (II) Oxide NaCl Sodium Chloride KI Potassium Iodide Mg3N2 Magnesium Nitride PbO2 Lead (IV) Oxide
Lewis Structures • A way to show the octet rule in molecules
Practice • Draw the lewis structures for • Ammonia (NH3) • Water (H2O) • Phosphorus Trifluoride (PF3) • Hydrogen Cyanide (HCN) • Ozone (O3) • Formaldehyde (CH2O)
VSEPR • AB5 • Trigonal bipyramidal • AB6 • Octahedral
VSEPR • AB4 • Tetrahedral • 109.50 Bond Angles • AB3 • Trigonal Planar • 1200 Bond Angles • AB2 • Linear • 1800 Bond Angles
VSEPR • AB2E • Bent or Angular • AB2E2 • Bent or Angular • AB3E • Trigonal Pyramidal
Polarity? • The potential for opposite charges at different areas of a molecule
Shape and Polarity? • What is the shape and polarity of the following molecules? • Water • Ammonia • Carbon Tetrachloride • Carbon Dioxide • Hydrogen Chloride
Hybrids • Atoms “don’t like” to have empty orbitals • Hybridization • Mixing of 2 or more atomic orbitals of similar energies to produce new hybrid orbitals of equal energies • It works like this • Methane: CH4 Normally: 1s22s22p2 • Through hybridization- it forms an “sp” orbital, with 4 electrons total • New arrangement: 1s22(sp3) 4
What type of hybrid? • Beryllium fluoride • BeF2 • sp • Ammonia • NH3 • sp2 • Methane • CH4 • sp3
Break Time Take a 10 minute break
Spectroscopy • Devices that measure the interaction between matter and energy • Absorption • Measures the wavelengths of electromagnetic waves absorbed by a substance • X-Ray spectroscopy • Used to determine elemental composition and types of bonding
Spectroscopy • UV • Used to quantify DNA and Protein concentration • Infrared • Used to determine bond type • Bonds resonate when exposed to the radiation • Nuclear Magnetic Imaging (NMR) • Used to determine bond structure
Simple Organics • Alkanes (end in –ane) • Containing only single bonds • CnH2n+2 • Alkenes (end in –ene) • Containing at least one double bond • CnH2n • Alkynes (end in –yne) • Containing at lease one triple bond • CnH2n-2
Naming and Formulas • Numbers are used in the name to designate locations of the following • Types of bonds • Branches • Attached functional groups • For Example • 2,2,4- trimethylpentane • 1-pentyne • 2,3,4- trimethylnonane • 2-methyl 3-hexene • 2- propanol
Macromolecules • Carbohydrates • Chains of carbon, hydrogen and oxygen. • Isomers • Lipids • Fatty acids- Chains of Carbon and Hydrogen • Proteins • Chains of Amino acids • Differ in their R group • Nucleic Acids • Chains of Nucleic Acids
Organic Compound Naming • Numbers are used in the name to designate locations of the following • Types of bonds • Branches • Attached functional groups • For Example • 2,2,4- trimethylpentane • 1-pentyne • 2,3,4- trimethylnonane • 2-methyl 3-hexene • 2- propanol
Lunch Time We start Again In ONE HOUR
Determining Empirical Formulas • Say you have 65.0g of compound containing Na and Cl. • Determine the Empirical Formula if the compound is 39.3% Na and 60.7%Cl
Higher Level Practice • 1st Step: Convert your percentages to mass of each element present • Na: (.393)(65.0g)= 25.545g Na • Cl: (.607)(65.0g) = 39.455g Cl
Higher Level Practice • 2nd Step: Determine number of moles of each element in the sample 25.545g Na 1 mole = 1.11 mol Na 22.989 g/mol 39.455g Cl1 mole = 1.11 mol Cl 35.453 g/mol
Higher Level Practice • 3rd Step: Use these moles to determine the smallest whole number ratio of elements to each other. That is your empirical formula! 1.11 mol Na : 1.11 mol Cl 1 mol Na : 1 mol Cl Empirical Formula = NaCl
Balancing Equations • __ C3H8 + __ O2 __ CO2 + __ H2O • __ Ca2Si + __ Cl2 __ CaCl2 + __ SiCl4 • __ C7H5N3O6 __ N2 + __ CO + __ H2O + __ C • __ C2H2 + __ O2 __ CO2 + __ H2O • __ Fe(OH)2 + __ H2O2 __ Fe(OH)3 • __ FeS2 + __ Cl2 __ FeCl3 + __ S2Cl2 • __ Al + __ Hg(CH3COO)2 __ Al(CH3COO)3 + __ Hg • __ Fe2O3 + __ H2 __ Fe + __ H2O • __ NH3 + __ O2 __ NO + __ H2O
Types of Chemical Reactions • Synthesis • A+B AB • Decomposition • AB A + B • Combustion • Burn in the presence of O2, to form dioxide gas, and other products **(CO2 + H2O) • Single Displacement • ACTIVITY SERIES • AB + C AC + B • Double Displacement • AB + CD AD + CB
Predict the Product CaO + H2O H2SO3 + O2 CaCO3 KClO3 C6H10 + O2 C6H12O6 + O2 Al + CuCl2 Ca + KCl Na2SO4 + CaCl2 KCl + NaOH Ca(OH)2 H2SO4 CaO + CO2 KCl + O2 CO2 + H2O CO2 + H2O AlCl3 + Cu No Reaction NaCl + CaSO4 KOH + NaCl
Identifying Redox Reactions Redox Redox Not Redox Redox Not Redox 2 KNO3(s) 2 KNO2(s) + O2(g) +1 -1 +1 -1 0 H2(g) + CuO(s) Cu(s) + H2O(l) 0 -2 +2 0 2(+1) -2 NaOH(aq) + HCl(aq) NaCl(aq) + H2O(l) +1 -1 +1 -1 +1 -1 2(+1) -2 H2(g) + Cl2(g) 2HCl(g) 0 0 +1 -1 SO3(g) + H2O(l) H2SO4(aq) +6 3(-2) 2(+1) -2 2(+1) -2
Balancing Redox Reactions • The following unbalanced equation represents a redox reaction that takes place in a basic solution containing KOH. Balance the redox reaction. Br2(l) + KOH(aq) KBr(aq) + KBrO3(aq)
Br2(l) + KOH(aq) KBr(aq) + KBrO3(aq) Ionic Reaction: Br2 Br- + BrO3- 0 -1 +5 3(-2)- Reduction ½ Rxn: Br2 Br- Br2 + 2e- 2Br- 5(Br2 + 2e- 2Br-) Oxidation ½ Rxn: Br2 BrO3- 12OH- + Br2 2BrO3- + 6H2O + 10e- Combined Rxn: 5Br2 + 12OH- + Br2 + 10e- 10Br- + 2BrO3- + 6H2O + 10e- 6Br2 + 12KOH 10KBr + 2KBrO3 + 6H2O 3Br2 + 6KOH 5KBr + KBrO3 + 3H2O
Standard Reduction Potentials in Voltaic Cells Write the overall cell reaction and calculate the cell potential for a voltaic cell consisting of the following half-cells: an Iron electrode in an Iron (III) Nitrate solution, and a Silver electrode in a Silver(I) Nitrate solution. • Fe3+(aq)+3e-Fe(s) E0=-0.04V • Ag+(aq)+e-Ag(s) E0=+0.80V • E0cell= E0cathode- E0anode • E0cell= (+0.80 V)- (-0.04 V)= +0.84 V • E0cell= positive = spontaneous
Acid/Base Properties • Strong Acids and Bases • Will ionize completely in a solvent • Weak Acids and Bases • Will ionize partially in a solvent • Buffer Systems • Solution containing a weak acid, and a salt of the weak acid • Acetic Acid and Sodium Acetate • Carbonic Acid and Bicarbonate
Break Time Take a 10 minute break
Mass-Mass Stoichiometry 3 Cu + 8 HNO3 3 Cu(NO3)2 + 4 H2O + 2NO • Copper Nitrate is used in creation of some light sensitive papers • Specialty photographic film • Your company needs 150 grams of Copper nitrate to fill an order. How many grams of Nitric Acid are needed to undergo reaction?
Step 3: Compute 150g Cu(NO3)2 1 mole8 mol HNO3 63.012 g = 187.554g 3 molCu(NO3)2 1 mole 134 g HNO3
Gas Stoichiometry Xenon gas reacts with fluorine gas according to the shown reaction. If a researcher needs 3.14L of XeF6 for an experiment, what volumes of Xenon and Fluorine should be reacted? Assume all volumes are measured under the same temperatures and pressures. Xe(g) + 3 F2(g) XeF6 (g)