• Significant Figures – start at the left and proceed to the right 1. If the number does not have a decimal point count until there are no more non zero numbers 2. If the number has a decimal point start counting at the first non-zero number and continue counting until you run out of decimal places • Vocabulary 1. Observation 17. Law of Conservation of Mass 33. percent weight 2. Hypothesis 18. Law of Conservation of Energy 34. percent error 3. Experiment 19. Exact numbers 35. percent composition 4. Theory 20. Accuracy 36. percent yield 5. Law 21. Precision 37. %RSD 6. Chemistry 22. compounds 38. limiting reactant 7. Matter 23. molecules 39. Stoichiometry 8. Energy 24. chemical formula 40. Stoichiometric Coefficient 9. Chemical Properties 25. empirical formula 41. Electron Affinity 10. Physical Properties 26. molecular formula 42. Electronegativity 11. Extensive Properties 27. structural formula 43. Covalent Bond 12. Intensive Properties 28. bond line formula 44. Ionic Bond 13. Scientific (natural) law 29. ball and stick model 45. Dipole 14. Anion 30. space filling model 46. London Dispersion Forces 15. Cation 31. mole 47. Resonance 16. Molecular Geometry 32. Electronic Geometry 48. Hybrid orbital 49. area of high electron density Table of Common Ions Common Positive Ions (Cations) Monovalent Hydronium (or hydrogen) Lithium Sodium Potassium Rubidium Cesium Francium Silver Ammonium Thalium Copper I H3O+ H+ Li+ Na+ K+ Rb+ Cs+ Fr+ Ag+ NH4+ Tl+ Cu+ Divalent Magnesium Calcium Strontium Beryllium Manganese II Barium Zinc Cadmium Nickel II Palladium II Platinum II Copper II Mercury II Mercury I Iron II Cobalt II Chromium II Lead II Tin II Mg2+ Ca2+ Sr2+ Be2+ Mn2+ Ba2+ Zn2+ Cd2+ Ni2+ Pd2+ Pt2+ Cu2+ Hg2+ Hg22+ Fe2+ Co2+ Cr2+ Pb2+ Sn2+ Trivalent Aluminium Antimony III Bismuth III Al3+ Sb3+ Bi3+ Iron III Cobalt III Chromium III Fe3+ Co3+ Cr3+ Table of Common Ions Common Negative Ions (Anions) Monovalent Hydride Fluoride Chloride Bromide Iodide Hydroxide Permangante Cyanide Thiocynate Acetate Nitrate Bisulfite Bisulfate Bicarbonate Dihydrogen phosphate Nitrite Amide Hypochlorite Chlorite Chlorate Perchlorate HFlClBrIOHMnO4CNSCNC 2H 3O 2NO3HSO3HSO4HCO3H2PO4NO2NH2ClOClO2ClO3ClO4- Divalent Oxide Peroxide Sulfide Selenide Oxalate Chromate Dichromate Tungstate Molybdate tetrathionate Thiosulfate Sulfite Sulfate Carbonate Hydrogen phosphate Trivalent Nitride O2O22S2Se2C2O42CrO42Cr2O72WO42MoO42S4O62S2O32SO32SO42CO32HPO42- Phosphate N3- PO43- Given or determined from balanced stoichiometric equation mass of molecule Molar Mass given or calculated from periodic table density molarity, ppm, molality, normality, etc. Vol solution Concentration solution Calculate from molecular formula or balanced equation moles of molecule Avogadro's Number Molar Ratio moles of element, or other reactant or product Number of molecules These concepts lead to solving problems determining limiting reactant and percent yield. Molar Mass given or calculated from periodic table Avogadro's Number Mass of element, or reactant or product Number of atoms, or molecules of reactant or product Quantum Numbers n and l define the energy of the electron The principal quantum number has the symbol ~ n which defines the energy of the shell n = 1, 2, 3, 4, ...... “shells” The angular momentum quantum number has the symbol ~ which defines the subshells. = 0, 1, 2, 3, 4, 5, .......(n-1) = s, p, d, f, g, h, .......(n-1) The symbol for the magnetic quantum number is m which defines the orbital. m = - , (- + 1), (- +2), .....0, ......., ( -2), ( -1), The last quantum number is the spin quantum number which has the symbol m s which characterizes the single electron. The spin quantum number only has two possible values. ms = +½ or -½ one spin up ↑ and one spin down ↓ Electrons: The Nucleus: Hund’s Rule states that each orbital will be filled singly Build by adding the required number of protons before pairing begins. The singly filled orbitals will have (the atomic number) and neutrons (the mass of the atom) a parallel spin. Pauli’s Exclusion Principle states that paired electrons in an orbital will have opposite spins. Fill the electrons in starting with the lowest energy level adhering to Hund’s and Pauli’s rules. Ionic Polar Covalent Covalent Determine Inductive effect Count the number of electrons the element should have Determine how equally electrons are shared (DEN) >1.7 consider it ionic Oxidation number Never Have a Full Octet Formal charge Always Have a Full Octet Sometimes Have a Full Octet Sometimes Exceed a Full Octet To calculate a formal charge 1. draw the Lewis dot structure 2. draw circles around each atom and the electrons associated with it. Remember that formal charges are associated with covalent bonds and that all electrons are shared equally. 3. compare to the group number for that atom. If the number is larger the formal charge is negative, smaller the formal charge is positive. To calculate an oxidation number 1. list all the elements follow with an equal sign 2. follow with the number of atoms of that type in the molecule 1. follow with a multiplication sign 2. If the element is O follow with a -2 3. If the element is H follow with a +1 4. any other element enter a ? 5. follow with an = sign, do the math 6. draw a total line, then enter the charge on the molecule 7. Do the algebra backwards to solve for ? VSEPR Theory Lone pair to lone pair is the strongest repulsion. 2 Lone pair to bonding pair is intermediate repulsion. 3 Bonding pair to bonding pair is weakest repulsion. • Mnemonic for repulsion strengths lp/lp > lp/bp > bp/bp • Lone pair to lone pair repulsion is why bond angles in water are less than 109.5o. Electronic geometry is determined by the locations of regions of high electron density around the central atom(s). Electron pairs are not used in the molecular geometry determination just the positions of the atoms in the molecule are used. Molecular geometry determined by the arrangement of atoms around the central atom(s). Summary of Electronic & Molecular Geometries Regions of High Electron Density Electronic Geometry Hybridization 2 Linear sp 3 Trigonal planar sp2 4 Tetrahedral sp3 5 Trigonal bipyramidal sp3d 6 Octahedral sp3d2 Isomers structural isomers constitutional isomers stereo isomers racemic mixture entantiomers geometric isomers positional isomers chiral molecules chiral centers optical isomers cis mer trans fac hydration isomers ionization isomers coordination isomers linkage isomers titration titrant primary standard secondary standard end point equivalence point pH oxidation numbers hydrocarbons unsaturated hydrocarbons saturated hydrocarbons alkanes alkenes alkynes aromatic compounds alkyls phenyls phenols alcohols esters ethers carbonyl groups aldehydes ketones carboxylic acids acyl chlorides organic halides amines amides resonance Arrhenius acids/bases Brönsted/Lowery acids/bases Lewis acids/bases Electrolytes Non electrolytes sugars polymers solvent concentration ppm wt% molecular equations ionic equations net ionic equations spectator ion metathesis reaction combination reaction decomposition reaction displacement reaction redox reaction addition polymerization condensation polymerization ligand donor atom unidentate polydentate chelate coordination number coordination sphere fats solution solute molarity ppb vol% Naming Saturated Hydrocarbons 1. 2 3 4 5 6 Choose the longest continuous chain of carbon atoms which gives the basic name or stem. Number each carbon atom in the basic chain, starting at the end that gives the lowest number to the first group attached to the main chain (substituent). For each substituent on the chain, we indicate the position in the chain (by an Arabic numeric prefix) and the kind of substituent (by its name). The position of a substituent on the chain is indicated by the lowest number possible. The number precedes the name of the substituent. When there are two or more substituents of a given kind, use prefixes to indicate the number of substituents. di = 2, tri = 3, tetra = 4, penta = 5, hexa = 6, hepta = 7, octa = 8, and so on. The combined substituent numbers and names serve as a prefix for the basic hydrocarbon name. Separate numbers from numbers by commas and numbers from words by hyphens. Words are "run together". Alcohols and Phenols • • • The stem for the parent hydrocarbon plus an -ol suffix is the systematic name for an alcohol. A numeric prefix indicates the position of the -OH group in alcohols with three or more C atoms. Common names are the name of the appropriate alkyl group plus alcohol. • Common names are used for most ethers. Ethers Aldehydes and Ketones • • • • Common names for aldehydes are derived from the name of the acid with the same number of C atoms. IUPAC names are derived from the parent hydrocarbon name by replacing -e with -al. The IUPAC name for a ketone is the characteristic stem for the parent hydrocarbon plus the suffix -one. A numeric prefix indicates the position of the carbonyl group in a chain or on a ring. Amines • • Amines are derivatives of ammonia in which one or more H atoms have been replaced by organic groups (aliphatic or aromatic or a mixture of both). There are three classes of amines. Carboxylic Acids • • IUPAC names for a carboxylic acid are derived from the name of the parent hydrocarbon. – The final -e is dropped from the name of the parent hydrocarbon – The suffix -oic is added followed by the word acid. Many organic acids are called by their common (trivial) names which are derived from Greek or Latin. When compounds contain more than one functional group, the order of precedence determines which groups are named with prefix or suffix forms. The highest precedence group takes the suffix, with all others taking the prefix form. However, double and triple bonds only take suffix form (-en and -yn) and are used with other suffixes. Functional group Formula Prefix Suffix 1 Cations e.g. Ammonium –NH4+ -onioammonio- -onium -ammonium 2 Carboxylic acids –COOH carboxy- -oic acid* 3 Carboxylic acid derivatives Esters Acyl chlorides Amides –COOR –COCl –CONH2 R-oxycarbonylchloroformylcarbamoyl- -oyl chloride* -amide* 4 Nitrites Isocyanides –CN –NC cyanoisocyano- -nitrile* isocyanide 5 Aldehydes Thioaldehydes –CHO –CHS formylthioformyl- -al* -thial* 6 Ketones Thioketones >CO >CS oxothiono- -one -thione 7 Alcohols Thiols –OH –SH hydroxysulfanyl- -ol -thiol 8 Amines –NH2 amino- -amine 9 Ethers Thioethers –O– –S– -oxy-thio- Priority Carbon Atom Hybridization C uses C forms Example sp3 tetrahedral 4 sp3 hybrids 4 bonds CH4 sp2 trigonal planar 3 sp2 hybrids & 1p orbital 3 bonds 1 bond C2H4 sp linear 2 sp hybrids & 2 p orbitals 2 bonds 2 bonds C2H2 Nomenclature 1. 2. 3. 4. 5. 6. 7. Rules for Naming Complex Species Cations (+ ions) are named before anions (- ions). Coordinated ligands are named in alphabetical order. – Prefixes that specify the number of each kind of ligand (di = 2, tri = 3, tetra = 4, penta = 5, hexa = 6, etc.) are not used in alphabetizing – Prefixes that are part of the name of the ligand, such as in diethylamine, are used to alphabetize the ligands. For complicated ligands, especially those that have a prefix such as di or tri as part of the ligand name, these prefixes are used to specify the number of those ligands that are attached to the central atom. – bis = 2 tris = 3 tetrakis = 4 pentakis = 5 hexakis = 6 The names of most anionic ligands end in the suffix -o. – Examples of ligands ending in –o are: • Cl- chloro S2- sulfido O2oxo The names of most neutral ligands are unchanged when used in naming the complex. – There are several important exceptions to this rule including: • NH3 ammine H2O aqua The oxidation number of a metal that exhibits variable oxidation states is designated by a Roman numeral in parentheses following the name of the complex ion or molecule. If a complex is an anion, the suffix "ate" ends the name. No suffix is used in the case of a neutral or cationic complex. Usually, the English stem is used for a metal, but if this would make the name awkward, the Latin stem is substituted. ferrate instead of ironate plumbate instead of leadate Ion/Molecule Name Name as a Ligand NH3 ammonia ammine CO carbon monoxide carbonyl Cl- chloride Chloro CN- cyanide cyano F- fluoride fluoro OH- hydroxide hydroxo NO nitrogen monoxide nitrosyl NO2- nitrite nitro PH3 phosphine phosphine System Arrhenius BrönstedLowry Lewis Acid (HCl) Base (NaOH) ∆H = Hfinal - Hinitial C5 H12( ) 8 O 2(g) 5 CO2(g) 6 H 2 O ( ) 3523 kJ 1 mole • 8 moles 5 moles 6 moles 1 mole The stoichiometric coefficients in thermochemical equations must be interpreted as numbers of moles. 1 mol of C5H12 reacts with 8 mol of O2 to produce 5 mol of CO2, 6 mol of H2O, and releasing 3523 kJ is referred to as one mole of reactions. ∆Horxn = ∆Hfo (prod) - ∆Hfo (react) Specific heat capacity (J/(g∙K) = cP = q m(Tf –Ti) heat lost or gained by system (Joules) mass(grams) DT (Kelvins) Variabl e Cp Tf Ti m q System 1 System 2 heat transfer in (endothermic), +q heat transfer out (exothermic), -q SYSTEM ∆E = q + w w transfer in (+w) w transfer out (-w) Heat Energy Internal energy Kinetic Energy Potential Energy Endothermic Exothermic Thermodynamics Thermal Equilibrium System Surroundings Law of Conservation of Energy Heat Capacity Specific Heat Capacity First Law of Thermodynamics Melting Freezing Deposition Sublimation Evaporation Condensation State Function Standard state temperature Standard state pressure Standard states matter Enthalpy Hess’s Law Thermochemical Equation Enthalpy of Formation Intramolecular forces Intermolecular forces Hydrogen Bonding Polarization Polarizability Vapor Pressure Equilibrium Heat of Vaporization Phase Diagram Solid Liquid Gas Triple Point Critical Point Super Critical Fluid Standard P 1.00000 atm or 101.3 kPa Standard T 273.15 K or 0.00oC n 2a V nb nRT P + 2 ( V K = 273 + oC 1 mm Hg = 1 torr 760 torr = 1 atm Variable The standard molar volume is 22.4 L at STP P (atm) PV = nRT R = 0.08206 L atm mol-1 K-1 Cond. 1 Cond. 2 0.08206 0.08206 V (L) N (moles) R (L atm mol-1 K-1) T (K) Ptotal = PA + PB + PC + ..... At low temperatures and high pressures real gases do not behave ideally. The reasons for the deviations from ideality are: 1. The molecules are very close to one another, thus their volume is important. 2. The molecular interactions also become important. • • • • • • • • • The Kinetic-Molecular Theory The basic assumptions of kinetic-molecular theory are: Postulate 1 – Gases consist of discrete molecules that are relatively far apart. – Gases have few intermolecular attractions. – The volume of individual molecules is very small compared to the gas’s volume. Proof - Gases are easily compressible. Postulate 2 – Gas molecules are in constant, random, straight line motion with varying velocities. Proof - Brownian motion displays molecular motion. Postulate 3 – Gas molecules have elastic collisions with themselves and the container. – Total energy is conserved during a collision. Proof - A sealed, confined gas exhibits no pressure drop over time. Postulate 4 – The kinetic energy of the molecules is proportional to the absolute temperature. – The average kinetic energies of molecules of different gases are equal at a given temperature. Proof - Brownian motion increases as temperature increases.