Antoine Lavoisier a French Chemist (1743-1794)



SOL Items Density formula D=m/v so for v= m/DVolume= L x W x H= units3 Area formula: L x W= units2 mass: m= D x vK=oC+273.16oC: K-273.16= oCPercent Error= (your value-literature value)/literature value x 100 (Units are in %)Energy Conversion of calories to joules: 0.2390 calories (cal) = 1 Joule (J) and 1 cal=4.184 JAtmosphere to Pascal: 1atm=101,305 PaPhysical Properties to remember: mass, length, volume, color, density, malleability, ductility, and conductivity, crystalline shape, melting point, boiling point, refractive index.Accuracy vs. Precision: Accuracy-Refers to how close the measurement is to the actual value while Precision refers to how close a set of measurements is together whether or not the measurements are correctSeparation of Mixtures:Distillation-occurs when a liquid is boiled to produce a vapor that is then condensed again to a liquid. This causes the solid substances that were originally dissolved to stay in the original container and the water to go into a second receiving container.Chromatography-Involves a solid (stationary phase) and a liquid or gas (mobile phase). The separation occurs because the liquid or gas has a faster rate than the solid. Paper Chromatography-paper (solid) and a liquid are involved. The liquid travels up the paper and separates according to the heaviness of the individual parts of the liquidAntoine Lavoisier a French Chemist (1743-1794)Proposed the Law of Conservation of Mass: in ordinary chemical reactions, matter can be changed in many ways, but it cannot be created or destroyed. Find on Periodic table: Atomic Number and Atomic Mass, and figure out Neutron #, Electron # and charge is negative, and Proton # and charge is positive.Atomic Mass (Symbol Z) –Atomic number (Symbol A)=neutrons Z-A=Neutrons (neutrons have no charge and are found in the nucleus with the protons)Note: Atomic number + neutrons =Atomic massAverage Atomic MassPercent (in decimal form) times Atomic Mass for each one and then add the total Rutherford's Gold Foil Experiment:That the atom is mostly empty spaceAnd that the nucleus is positive charged (because of protons) and contains almost all of the mass of the atom.Alpha radiation is radiation that was deflected toward the negatively charged plate alpha radiation. Made up of 2 alpha () particlesEach alpha particle contains 2 protons and 2 neutronsHas a 2+ chargeHas a mass of 4 amu Ex.: Ra- 88 (Radium-226) 86 Rn (radon-222) + 4 He (alpha particle) (Exact model will be shown in class)Beta radiation is radiation deflected toward the positively charged plate beta radiation.Consist of fast moving electrons known as beta () particles.Each beta particle contains an electron with a -1 charge.Ex.: C-14/6 14N/7 + 0/+1e Half Life FormulaAmount Remaining= Original Amount of parent ÷ 2n n=half-lifeElectron Configuration-The arrangement of electrons in an atom. The order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p, 8sRules:Octet law: only a maximum of 8 electrons on the outermost shell (2 in the 1st level)-known as the valance electron numberThe aufbau principle states that each electron occupies the lowest energy orbital availableIn order of increasing energy, the sequence of energy sublevels within a principal energy level is s (2 e-), p (6 e-), d (10 e-), and f (14 e-).The Pauli exclusion principal states that a maximum to 2 electrons may occupy a single atomic orbital, but only if the electron has opposite spins. Represented as ↑↓Periodic Trends: Atomic Radius-Deals with the size of an atomIt decreases as it moves across a periodIncreases as it moves down the GroupElectronegativity-The attraction it has to bond with other elements- F has the highestIt decreases as it moves down a group and increases as it moves across a periodPeriodic table/Element items:Dmitri Mendeleev put together the 1st periodic table-Table not completely correctA period in the periodic table is all the elements in a horizontal row.A group in the periodic table is all the elements located in the same vertical column, which is assigned a number from 1-18. METALSUsually shiny when smooth and cleanConduct heat and electricity wellSolid at room temperatureMost are also ductile and malleable (meaning they can be pounded into thin sheets and drawn into wire.)Chemically reactivePositively chargedThese atoms have only a few electrons in the outer level. Have a tendency to lose their electrons in the outermost level.Alkali metals: Group 1 except HThey react with waterEasily lose a valence electron and form an ion with a +1 charge.Ends in sublevel s1Alkaline Earth metals: Group 2Reactivity similar to Alkali metals but not as great+2 chargeEnds in sublevel s2Aluminum Group (Sometimes called the Boron Group)Group 13 +3 chargeTransition Elements for divided into 2 set:Transition metalsAny element in columns 3-12 Has 2 electrons in the outer level - 4s2Elements with #'s 22-28 also have a 3d sublevelIn all groups except 12, the d orbitals are only partially filled. Share properties such as electrical conductivity, luster, and malleability with other metals.They have magnetismInner transition metals: Lanthanoid Series and Actinoid SeriesThey are the highest energy electrons (f electrons) are inside the d sublevel and the outer level.Both have outer shells consisting of an s2 sublevelLanthanoid Series- Lanthanum (57) to Ytterbium (70)Electrons are added to the 4f sublevel instead of the sixth or outer levelAre silvery metals with relatively high melting pointsUsed extensively as phosphors, substances that emits light when struck by electrons.Actinoid Series-Actinium (89) to Nobelium (102)This series have an increasing # of electrons in the 5f sublevelThey are all radioactive.NONMETALSThese are usually gases or brittle solids at room temperature.Dull appearanceInsulatorsOuter electrons are held closely by the nucleusForm negative ions (anions)Have 5 or more electrons in the outer level than metals.They often gain electrons or share their electrons in the outermost level.Group 14: Carbon GroupAllotropes are found in this group: forms of an element in the same physical state that have different structures and properties. Ex. Carbon in the form of coal, Diamonds and graphiteSilicates are silicon compounds bound to Oxygen, and each Si atom is surrounded by 4 O atoms.Group 15: The Nitrogen and Phosphorus GroupThere are nonmetals (N and P), metalloids (As and Sb), and metals (Bi) Each has 5 valence electrons and have many different propertiesCharge is -3Group 16: The Oxygen Group or ChalogensHave 2 allotropes: Ozone, and O2Some are oxides known as amphoteric: Those that can produce either acidic or basic solutions. Ex. Sulfur compounds like sulfuric acid (H2SO4)Charge is a -2The highly reactive Group 17 elements are called HalogensFluorine is the most reactive element- Highly electronegativityHalogens make saltsHave 7 valence electrons and often tend to share one electron or gain one.Have a 1- charge so they react with Group 1 the mostThe extremely nonreactive Group 18 and is known as Noble gases.All except Helium have 8 electrons in their outer level. METALLOIDSThese are elements with physical and chemical properties of both metals and nonmetals. Silicon and germanium are used a lot in making computer chips and solar cells.Staircase elements between metals and nonmetalsAre often brittle solidsOxidation NumberFor metals Positively chargedin Group 1-2: Same as Group number in Groups 3-12: number varies Ex. Hydrogen is in Group 1 and the Oxidation # is +1Ex. Magnesium is in Group 2 and the Oxidation # is +2For nonmetalsNegatively chargedFind valence electron number: 2nd number of group #Formula: -8+valence electron numberEx. Oxygen is in Group 16, -8 + 6= -2Ex. Nitrogen is in Group 15, -8 + 5= -3Ex. Chlorine is in Group 17, -8 + 7= -1For MetalloidsPositively chargedFind the number the same way and nonmetalsEx. Carbon is in Group #14 and the Oxidation # is +4Ionic Bond NotesPropertiesIonic Bonds are formed by a cation (positive charged metal) bonded to an anion (negative charged nonmetal)Metal loses one or more electronsNonmetal gains one or more electronsNote: Static electrical attraction is the basis for ionic bonds, because the positively charged ion (cation) is attracted to the negatively charged ion (anion)High Boiling and High Melting pointForms a 3-D crystal latticeCrystal lattice bonds are strong and take lots of energy to break the bondsUsually poor conductors of electricityBecause they are solid and rigid the ions can’t move freelyOnly good conductors if dissolved in an aqueous solution where they become electrolytesDon’t consist of moleculesStrongly bondedCan form a saltIonic TermsIon: charged particleAnion: negatively charged ionCation: Positively charged ionSalt: An ionic compound that forms when a metal atom or a positive radical replaces the H of an acid. Ex. NaClSalts are excellent conductors of electricity because they are brittle solids that can easily be dissolved in an aqueous solution such as water Ionic Bonding Problems/Diagrams Na (+1) + Cl (-1) → NaClCa (+2) + Cl (-1) +Cl (-1) → CaCl2Naming Ionic CompoundsMany Ionic compounds contain polyatomic ions: ions made up of more than one atom.Polyatomic ions exist as a unit, so never change the subscriptIf you have to balance an ionic compound with a polyatomic ion then ( ) and a subscript must be writtenEx. Ca (+2) and PO4 (-3) →Ca3(PO4)2 and named Calcium phosphateMost polyatomic ions are oxyanionsOxyanion is a polyatomic ion composed of an element, usually a nonmetal, bonded to one or more oxygen atomsIf a transitional metal and a polyatomic ion is involvedEx. Cu (+2) and NO3 (-1) →Cu(NO3)2 and named Copper (II) nitrateNote that transitional metals with varying oxidation numbers always have to state which atom was used in the chemical compound whether or not a polyatomic ion is usedRules for Naming Ionic CompoundsName the cation (metal) first and the anion (nonmetal) secondMonatomic cations use element nameMonatomic anions take their name from the root element name plus the suffix –ideEx. CsBr is Cesium bromideDetermine oxidation numbers of transitional metals compounds before naming to determine Roman number I-IVEx. Fe2O3 is Iron (III)oxideSome transitional metals only have one chargeCadmium: Cd+2Zinc: Zn+2If the compound has a polyatomic ion, simply name the ionEx. NH4Cl is Ammonium chlorideIf the polyatomic ion has an oxyanionsThe ion with more oxygen atoms is named using the root of the nonmetal plus the suffix –ateEx. NO3- is nitrateEx. ClO3- is chlorateEx. CO3-2 is carbonateThe ion with fewer oxygen atoms is named using the root of the nonmetal plus the suffix –iteEx. NO2- is nitriteThe oxyanions with the greatest number of oxygen atoms is named using the prefix per-, the root of the nonmetal, and the suffix-ateClO4- is perchlorateIO4- is periodateMnO4- is permanganateThe oxyanions with one less oxygen atom is named with the nonmetal and the suffix-ateSO4-2 is sulfateThe oxyanions with two fewer oxygen atoms is named using the root of the nonmetal plus the suffix –iteEx. ClO2 – is chloriteThe oxyanions with three fewer oxygen atoms is named using the prefix hypo-, the root of the nonmetal, and the suffix –iteEx. ClO – is hypochloritePolyatomic ions with 2 transitional metal atoms include a Di-prefixEx. H2PO4- is Dihydrogen phosphateEx. Cr2O7-2 is DichromateSome Hydrogen plus a polyatomic ion are named two waysEx. HSO4- can be named bisulfate or Hydrogen sulfateEx. HCO3- can be named bicarbonate or Hydrogen carbonateCovalent BondsPropertiesNonmetal + Nonmetal (usually)Most common type of bondCovalent bonds form moleculesForm by sharing electrons The sharing of one pair of electrons is a single bond (X-X)Another name for single covalent bond is sigma bond symbolized by σSigma bonds form from the overlap of a s orbital with another s orbital, a s orbital with a p orbital, or a p orbital with another p orbitalThe sharing of two pairs- double bond (X=X) Another name for multiple bonds is pi bond symbolized by πPi bonds form when parallel orbitals overlap to share electronsA double covalent bond has one sigma and one pi bondThe sharing of three pairs-triple bond (XΞX)A triple covalent bond has one sigma and 2 pi bondsBond polarity explains the attraction between the sharing Nonpolar electrons are shared equally Ex. F-F (same electronegativity)Polar electrons are not shared evenly Ex. H-F (different electronegativity) Intramolecular Forces in Bonds TableForce Basis of attractionIonic cations and anionsCovalent positive nuclei and shared electronsMetallic metal cations and mobile electronsIntermolecular ForcesIntramolecular forces do not account for all attractions between particles. There are forces of attraction called intermolecular forces.They can hold together identical particles or two different types of particlesAlso called van der Waals forces3 types:Dispersion forcesSometimes called London dispersion forcesThe force between oxygen moleculesWeak forces that result from temporary shifts in the density of electrons in electron clouds: δ- δ+δ- δ+ δ+ δδ+ δ+ δ+ δ= δ+……… Attraction Temporary attraction Temporary attraction ←|-←|-Dipole –dipole: Attraction between oppositely charged regions of polar moleculesStronger than dispersion forcesThe more polar the molecule, the stronger the forceHydrogen bonds: One special type of dipole-dipole dealing with hydrogen bondsVery strong intermolecular force that is formed with a H end and a F, O, or N atom on the other dipoleMany physical properties of covalent molecular solids are due to intermolecular forces.The melting and boiling points are relatively lower than Ionic (that is why salt doesn’t burn when you heat it but sugar will)Many are gases are vaporized at room temperatureHardness is also due to the intermolecular forces so covalent solids are soft in comparison to ionic solidsNaming Molecular Compounds: Rules for Binary Molecular Compounds are similar to that of naming Ionic compounds except the names include prefixes indicating the number of atoms in the molecule.Numerial PrefixesMono-1Di-2Tri-3Tetra-4Penta-5Hexa-6Hepta-7Octa-8Nona-9Deca-10Exceptions: H2O is waterNH3 is ammoniaExamples:CO2 –Carbon dioxideCO-Carbon monoxideN2O4-dinitrogen tetroxideSCl6 –Sulfur hexachlorideNaming Acids and BasesBinary acids are acids with only two elements.Prefix –hydro, stem of anion, and suffix –icException is HN3: Hydroazoic acid, where the root – azo is used for nitrogen.Ternary acids are acids that contain 3 elements.Usually no prefix is used and the suffix is –ic.Exceptions:One less O than the most common : no prefix and suffix used is –ousTwo less O than the most common: prefix hypo- and suffix –ousOne more O than the most common: prefix per- and suffix –icEx. HClO3 is the most common: Chloric acidHClO2 has one less O so: Chlorous acidHClO has two less O so: Hypochlorous acidHClO4 has one more O than most common so: Perchloric acidTernary basesArrhenius bases are composed of metallic, or positively charged ions and the negatively charged hydroxide ion. Therefore, these bases are named by adding the word hydroxide to the name of the positive ion. Ex. Sodium hydroxide is NaOH.Characteristics of Acids and BasesAcidsLiquids are tart, sour, or sharp tastingThey conduct electricity (in solutions)-electrolytesThey produce H2 gasUsually in liquid or gas formpH is 0-6.9 Strong acid-have a low pH and completely ionized in an aqueous solutionThe closer the substance’s pH is zero the stronger the acidWeak Acid-have pH closer to 6.9 and are only slightly ionized in an aqueous solutionThey react to metals-corrosiveBasesCommonly found in solid formChemical formula except for NH3 has OH on the endpH range is 7.1-14Strong base-dissociates completely into metal ions and OH- ions in aqueous solutionThe closer the substance’s pH is 14 the stronger the baseSome are not very soluble in waterWeak base-react with water to form the OH- ion and conjugate acid of the baseSome are insoluble in water while others are solubleSlippery feel because bases react with oils in your skin-soaps and cleaning agentsAre electrolytesThree primary theories of acids and bases TheoryAcid definitionBase DefinitionArrheniusAny substance that releases H+ ions in water solutionAny substance that releases OH- ions in water solutionBronstead-LoweryAny substance that donates a protonAny substance that accepts a protonLewisAny substance that can accept an electron pairAny substance that can donate an electron pairExamples:Arrhenius acid: HCl (g)→H+(aq) +Cl-(aq) Arrhenius base: NaOH (cr) →Na+ (aq) + OH-(aq)Bronstead-Lowery: HCl (g) + H2O → H3O+(aq) + Cl-(aq)Acid +base→conjugate acid + conjugate baseConjugate acid-is the particle formed when a base gains a H+ ionConjugate base-is the particle that remains when an acid has donated a H+ ionConjugate acid-base pair-consists of 2 substances related by the gain or loss of a single H+ ionLewis: H3N: (Lewis base) + BF3 (Lewis acid) → H3N: BF3 (Product)pHpH is a measurement of the H3O+ ion concentration of an acid or a base.Problem Formulas: (Actual problem examples will be stated in class)pH=-log[H+]pOH=-log[OH-]pH + pOH=14[H3O+]=10-pH use antilog[OH-]=10-pH[OH-]=antilog (-pOH)Kw=[OH-] x [H+] which equals 1 x 10-14MTitrationTitration-is a procedure used to bring a solution of a known concentration into a reaction with a solution of an unknown concentration in order to determine the unknown concentration or the quantity of the solute in the unknown.The point in the titration at which stoichiometrical equivalent quantities of reactants are brought together –equivalence point An indicator can be used to show the end point of the titration, (at equivalence point)In acid-base titrations, the dyes used are colorless and only change to pink (basic) or blue (acidic) at the end pointExample dyes are phenolphthalein colorless for an acid and pink for a base, and NaOH blue with acids and pink for baseThe neutralization reaction occurs between an acid and a metal OH (base) and produces water and a salt (is a crystalline compound composed of the negative ion of an acid and the positive ion of a base.)Empirical and Molecular FormulasEmpirical Formula: The smallest whole number mole ratio of elements in a compoundAssume that each percent by mass represents the mass of the element in a 100.00-g sampleHow to Calculate Empirical Formula1st: Calculate the % composition of each element (If not given) and change % into grams2nd: Calculate Molar Mass of each element3rd: Determine simplest whole # ratio4th: Write Empirical FormulaExample #1The mass of C is 48.64g, the mass of H is 8.16g, and the mass of O is 43.20g. Find the Empirical Formula (EF).Step 1: Find Molar mass of each element48.64 g of C X 1 mol of C/12.01g of C (atomic mass) =4.050 mol of C8.16 g of H X 1 mol of H/1.008g of H (atomic mass) =8.10 mol of H43.20 g of O X 1 mol of O/16.00g of O (atomic mass) =2.700 mol of OStep 2: Determine simplest ratio by dividing the lowest amount of moles determined in step 14.050/2.7 = 1.5 mol of C 8.10/2.7 = 3 mol of H2.7/2.7 = 1 mol of OThen look at the three numbers of moles and determine the lowest number they can be multiplied by to get all whole numbers. In this case the number is 2.4.050/2.7 = 1.5 mol of C x2=3 mol of C8.10/2.7 = 3 mol of H X 2=6 mol of H2.7/2.7 = 1 mol of O X2=2 mol of OStep 3: Create Empirical Formula from moles in Step twoC3H6O2Example #2Succinic acid is a substance produced by lichens. Chemical analysis indicates it is composed of 40.68% C, 5.08% H, and 54.24% oxygen and has a molar mass of 118.1g/mol. Determine the empirical formula for succinic acid.Step 1: Determine molar mass.1st: Convert percentages into grams of elements.2nd: Use molar mass formula to find moles.40.68 g of C X 1mol C/12.01g (atomic mass) of C= 3.390 mol of C5.08 g of H X 1mol H/1.008g (atomic mass) of H=5.04 mol of H54.24g of O X 1mol O/16.00g (atomic mass) of O=3.390 mol of O Step 2: Determine simplest ratio by dividing the lowest amount of moles determined in step 13.390/3.390 = 1 mol of C 5.04/3.390 = 1.5 mol of H3.390/3.390 = 1 mol of OThen look at the three numbers of moles and determine the lowest number they can be multiplied by to get all whole numbers. In this case the number is 2.3.390/3.390 = 1 mol of C X 2 =2 mol of C5.04/3.390 = 1.5 mol of H X 2=3 mol of H3.390/3.390 = 1 mol of O X 2 =2 mol of OStep 3: Create Empirical Formula from moles in Step two: C2H3O2Percent Composition% Composition formula: Mass of element/ Mass of Compound X 100 = % of mass in gramsNote: You may only be given the name of the compound and not the formula. If so, you will have to use your rules you learned from Ionic and Covalent Bonds. Example #1Find the percent composition by mass of Hydrogen and Oxygen in water. (Formula: H2O)Step one: Find individual mass (if not already stated in problem) of elements# of Atoms of H: 2 (also called # of moles)2 atoms of H X Atomic mass of H 2X1=2 g of H# of Atoms of O: 1 (also called # of moles)1 atom of O X Atomic mass of O 1X16=16 g of OStep two: Find Mass of Compound (if not already stated in the problem)2X1= 2 g of H1X16=16 g of O 18g/mol of H2O (just add individual amounts together)Step three: Use Percent Composition formula to solve problem2.0 g of H/18.0g of H2O X 100= 11% of H16g of O/18g of H2O X 100= 89% of OExample #2Find the percent composition of each element in Sodium Hydrogen Carbonate.Step one: Figure out chemical formula: NaHCO3Step two: Find individual mass (if not already stated in problem) of elements# of Atoms of Na: 1 (also called # of moles) 1 atom of Na X Atomic mass of Na 1X23=23 g of Na# of Atoms of H: 1 (also called # of moles) 1 atom of H X Atomic mass of H 1X1=1 g of H# of Atoms of C: 1 (also called # of moles) 1 atom of C X Atomic mass of C 1X12=12 g of C# of Atoms of O: 3 (also called # of moles) 3 atoms of O X Atomic mass of O 3X16=48 g of OStep three: Find Mass of Compound (if not already stated in the problem)1X23=23 g of Na1X1= 1 g of H1X12=12 g of C3X16=48 g of O 84g/mol o NaHCO3 (just add individual amounts together)Step four: Use Percent Composition formula to solve problem23 g of Na/84.0g of NaHCO3 X 100= 27.3% of Na1.0 g of H/84.0g of NaHCO3 X 100= 1.190% of H12 g of C/84.0g of NaHCO3 X 100= 14.28% of C48g of O/84.0g of NaHCO3 X 100= 57% of OLewis Dot-1-8 dots according to valance electron #Molecular Molecules (drawn chemical structures)-VSEPRNaming types and Balancing Chemical Equations Stoichiometry Formulas: Also include Limiting Reagent and Percent YieldMoles to Moles: Given Moles x mole ratioMoles to Mass: Given Moles x mole ratio x (Molar mass of unknown ÷ 1 mol of unknown)Note – Any Stoichiometry problem dealing with Mass must be in grams. Sometimes you have to convert into Grams (In Mass to Mass problems)Moles to Volume (using STP): Given Moles X Mole ratio X (22.4 L of unknown ÷1 mol of unknown)Mass to Moles: Given Mass x (1 mol of known ÷ Molar Mass of known) x Mole ratio Mass to Mass: Given Mass x (1 mol of known ÷ Molar Mass of known) x Mole ratio x (Molar mass of unknown ÷ 1 mol of unknown)Mass to STP Volume: Given Mass x (1 mol of known ÷ Molar Mass of known) x Mole ratio x (22.4 L of unknown ÷1 mol of unknown)Volume to Volume-Density: Given Volume x Density of given (g/L) x (1 mol of given÷ Molar mass of given ) x mole ratio x (unknown Molar mass ÷ 1 mol of unknown) x Density of unknown (but one liter of unknown ÷ grams) Volume to Volume using just STP: Given volume x (1 mol of known ÷22.4 L) x mole ratio x (22.4 L of unknown ÷ 1 mol of unknown)Molecules to Molecules: Given molecules x (1 mol of given ÷ 6.022 x 1023 of given molecules) x mole ratio x (6.022 x 1023 of unknown molecules ÷ 1 mol of unknown) Molecules to Grams: Given molecules x (1 mol of given ÷ 6.022 x 1023 of given molecules) x mole ratio x (molar mass of unknown ÷ 1 mol of unknown) Thermochemistry and Chemical KineticsLaw of Conservation of Energy: In any chemical reaction or physical process, energy can be converted from one form to another, but neither can be created or destroyedHeat-The energy transferred between objects that are at different temperaturesIt is an extensive property, which means that the amount of the energy transferred as heat by a sample depends on the amount of the sampleTemperature-a measure of how hot (or cold) something is, specifically it is a measure of the average kinetic energy in the particles of an objectIt is an intensive property, which means that the temperature of a sample does not depend on the amount of the sampleEnthalpy- represented as H, is the total energy content of a sample. If pressure remains constant the enthalpy increases in a sample of matter equal to the energy as heat that is received.Molar Heat Capacity- (C) in a pure substance it is the energy as heat is needed to increase the temperature of one mole of a substance by 1 Kelvin. Calorimetry-the measurement of heat related constants, such as specific heatCalorimeter-a device used to measure the heat absorbed or released in a chemical or physical changeEntropy (S) is a measure of randomness or disorder in a system and is a thermodynamic propertyMeasuring Heat Calories- The amount of heat required to raise the temperature of one gram of pure water by one degree Celsius. kcal = 1000 caloriesSI units of heat and energy is joules (J)One J=0.2390 calOne cal=4.184 JKJ=1000 JoulesSpecific Heat is the amount of heat required to raise the temperature of on g of that substance by one degree C. Basic Equation q=C x m x ΔT q= the heat absorbed or releasedC (sometimes seen as Cp) =the specific heat (also called Molar heat capacity)m=mass in gΔT = change in temperature in oC ΔTLots of variationsn (number of moles)= q ÷ C ΔTn= mass (m) ÷ Molar mass (M) n=m ÷ Mc (calorie) =C ÷ MΔT =Tf (Final temp) – Ti (Initial Temp)ΔH (Change in Heat) = C x ΔTq= n x C x ΔTC = q ÷ n x ΔTΔT = q ÷ n x CChemical Kinetics-The Study of Reaction Rate (Also see Unit 10 booklet and textbook-Chapter 16) Activation Energy-The minimum amount of energy required to start a chemical reaction Exothermic reactions- the products are lower energy level than the reactants (makes chemical reactions rise in temperature) so the ΔH is negativeEndothermic reactions- The energy of the products is greater than the reactants (chemical reaction lowers in temperature) so the ΔH is positiveCatalyst –speeds up a reaction by providing the reactants with an alternate pathway that lowers the activation energyInhibitor-slows down and can stop a reactionSolubility CurvesPhase DiagramsGas LawsP = Pressure T= Temperature V= Volume1atm=101.3 kPa760 mm Hg =101.3 kPaso 1atm=760 mm Hg760 torr=1 atmManometers are used to measure the pressure in a closed containerSTP: T =273.16 K and 1 atm of pressure or 101.3 kPaBoyle’s Law: P1V1=P2V2 Charles’ Law: V1/T1=V2/T2Gay Lussac’s Law: P1/T1=P2/T2Combined Gas Equation: P1V1/T1=P2V2/T2Dalton’s Law of Partial Pressures: PT (total) = P1 + P2 +etcIdeal Gas Law: PV = nRT R = 8.314L x kPa / mol x K or R = 0.0821 atm x L / mol x KAmount of gas (n) = moleM=Molar mass g/molm=molesBoiling point depression Formula: iKbm 5 stepsDetermine the moles of soluteFind Molality Add grams of solution together if neededconvert g into kgthen find molalityAdd up the # of ions present (add up subscripts if Ionic or put one for Covalent compound)i (# of ions) x Kb of solvent x Molality = Kb Change in Kb (?Kb) = Boiling point of solvent + answer in step 4Example: What is the expected boiling point of CaCl2 solution containing 385g of CaCl2 in 1230g of water? (Kb of water is 0.51oC and the Boiling point of water is 100oC)1st: 385g of CaCl2 x 1mole of CaCl2/110.8g of CaCl2 =3.47 moles of CaCl22nd: m=moles of solute/kg of solution 3.47moles/1.230kg of H2O=2.82 m3rd: Ionic so add subscripts CaCl2 1+2=34th: 3 x 0.51 x 2.82=4.3146 oC5th: 100 + 4.3146=104.3146 oC is ?KbFreezing point depression Formula: iKfm 5 stepsDetermine the moles of soluteFind Molality Add grams of solution together if neededconvert g into kgthen find molalityAdd up the # of ions present (add up subscripts if Ionic or put one for Covalent compound)i (# of ions) x Kb of solvent x Molality = Kb Change in Kf (?Kb) = Freezing of solvent + answer in step 4M (Molarity)=mole of solute ? Liter of solutionm (Molality)= mole of solute ? Kilograms of solutionMolarity with Dilution FormulaFormula: M1V1=M2V2 M=Molarity and V=VolumeConvert Volume to LitersExample: How much 16M HCl is needed to prepare 200mL of 5M solution?Solve: 16M x .2L =5M x V2 (?) 3.2=5V2 so V2= .64L needed 55Keq and Ksp problemsScientific NotationSignificant DigitsConversion of Metric UnitsAdd: Chemical and Physical changeChemical PropertiesLab safetyScientific methodValence electronsActual pH scale (pH mentioned but not the scale itself)Properties of gasesHeat of fusion ?Hf x massHeat of vaporation ?Hv x massParts of solutions: solute (what is being dissolved) solvent (what is dissolving the solute)Kinetic molecular theoryAverage kinetic theory of water increases as the temperature increases energyGases have the highest entropyExothermic vs. endothermic Graph ................
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