AP Notes, Outlines, Study Guides, Vocabulary, Practice Exams and more!

AP Chemistry (Comprehensive) Flashcards

Terms : Hide Images
6303098014mass spectrometry-can be used to determine the mass of various isotopes of a substance0
6303098015percent compositionmass of element / mass of compound1
6303098016empirical formulasimplest ratio of a compound2
6303098017molecular formulaactual formula for a substance3
6303098018Aufbau principleelectrons occupy lowest available energy level4
6303098019Pauli Exclusion Principlewithin an atom no 2 e- can have the same set of quantum numbers; if an orbital has 2 e-, they must have different spins5
6303098020Hund's Rulewhen an e- is added to a subshell, it will always occupy an empty orbital if avaliable6
6303098021quantized energy levels-e- can only exist at specific energy levels -as they get farther from the nucleus, their potential energy increases7
6303098022Coulomb's law-can calculate the energy an atom has based on its distance from the nucleus -greater the charge of the nucleus, the more energy the e- will have -the closer the e- to the nucleus, the more energy the e- will have8
6303098023Quantum Theoryenergy changes occur in steps9
6303098024Bohr Model-electrons are present in specific energy levels -when e- gain energy, they move up energy levels, while e- release energy as they move down10
6303098025energy/ wavelength/ frequencyE = hv = hc / λ -E = energy change -h = Plank's constant-6.63 x 10^-34 -v = frequency -λ = wavlength -c = speed of light 3.00 x 10^8 -higher frequency and short wavelength means more energy11
6303098026frequency and wavelengthc = λv -c = speed of light-3.00 x 10^8 -λ = wavelength -v = frequency12
6303098027ionization energy (aka binding energy)-amount of energy necessary to remove an e- from an atom; related to effective nuclear charge -↑ across a period -↓ down a group -second i.e. > first i.e. -i.e. gradually increases each successive time, until the outer shell is empty, then it increases a lot13
6303098028kinetic energy-energy of motion14
6303098029photoelectron spectra (PES)-amount of ionization energy for all e- ejected from a nucleus -graph that charts the binding/ionization energy against the number of electrons -each peak in the graph represents an subshell15
6303098030electron configuration-use the periodic table to do this; note that the p's start w/ 2, d's w/ 3, and f's with 4 -shorthand method: write noble gas to stand for the configuration up to that element16
6303098031John Dalton-said there are different types of atoms, called elements -elements combine, forming compounds -compounds have the same ratio of elements -atoms are never created or destroyed in chemical reactions17
6303098032J.J. Thomson-cathode ray experiment -put forth plum pudding model18
6303098033Millikan-created oil-drop experiment to find the mass and charge of an individual electron19
6303098034Rutherford-gold foil experiment→fired alpha particles @ gold foil and saw how they scattered -concluded that: (1) atom was mostly empty space (2) all the positive charge was concentrated in the middle of the atom20
6303098035Heisenberg Uncertainty Principle-it is impossible to know both the position and velocity of an e- @ any given moment21
6303098036electron attractedness-↑ attraction when closer to nucleus -↑ attraction when more protons in nucleus -repelled by other e-22
6303098037metals-left hand side of periodic table -give up e- in ionic bonds23
6303098038non-metals-upper right hand of periodic table -gain e- in ionic bonds24
6303098039atomic radius-↓ across a period -↑ down a group -cations < atoms -anions > atoms25
6303098040electronegativity-atom's ability to pull electrons toward itself when involved in a chemical bond -↑ across a period -↓ down a group26
6303098041ionic bond-electrostatic attraction between ions (e- are given up, creating ions) -creates a lattice structure; greater the charges and smaller the ions, greater the lattice energy -high melting/boiling points27
6303098042metallic bonds-metals can bond with themselves, forming a sea of electrons -metals can bond with other metals, forming alloys; alloys are interstitial if between atoms w/ vastly different radii or substitutional when between atoms w/ similar radii28
6303098043covalent bonds-2 atoms share electrons29
6303098044conductors: ionic compounds-ionic solids do not conduct electricity -ionic liquids do conduct electricity30
6303098045sigma (σ) bond-first covalent bond31
6303098046pi (π) bond-2nd and 3rd bonds in a covalent compound32
6303098047as the number of covalent bond increases...-...the bond length decreases -...the bond energy increases33
6303098048polar covalent bond-e- are unequally shared b/c atoms have different electronegativities; greater the difference in electronegativities, more polar the bond -molecule has dipole moment34
6303098049Intermolecular forces-aka IMF's -only exist in covalently bonded molecules -includes network covalent bonds, hydrogen bonds, dipole-dipole forces, and london dispersion forces35
6303098050network covalent bond-lattice of covalent bonds; usually occurs w/ carbon or silicon -poor conductors of electricity -highest melting and boiling points36
6303098051hydrogen bond-like a dipole-dipole, but stronger -hydrogen end of molecule attracted to F/O/N -high melting/boiling points37
6303098052dipole-dipole force-positive end of one polar molecule attracted to negative end of another -greater the polarity, greater the dipole-dipole -low melting/boiling points38
6303098053London Dispersion Forces (LDF's)-weak attraction due to e- movement that forms a temporary dipole -larger the molecule, larger the LDF -low melting/boiling points39
6303098054How to Draw a Lewis Structure1. count up number of total valence e- (add e- for anions; subtract for cations); this is how many e- should be in your final answer 2. draw molecule w/ bonds so that each molecule has full octet40
6303098055electron-deficient-Boron--> only needs 6 e- to be stable (BF₃) -Beryllium--> only needs 4 e- (BeCl₂)41
6303098056exceeding octet rule-element must be in 3rd period or higher -exceeds by using d orbital -ex--> SF₆, PCl₅, XeO₃, ICl₄⁻, ClF₃42
6303098057resonance form-occurs when 2+ Lewis structures can be made for a molecule -can be flipped to resemble each other -'real' molecule is an average of these structures43
6303098058formal charge-(normal valence e- # for atom) - ((# of lone pair e-) + 1/2(# of shared e-)) -sum of the formal charges must = the charge of the molecule/ion -negative formal charges should reside on the most electronegative atom -the best Lewis structures have mostly 0 formal charges44
6303098059VSEPR Model-model used to predict molecular geometry -double/triple bonds treated same way as single bonds -lone e- pairs occupy more space than bonding pairs45
6303098060linear-2 e- groups -180° apart46
6303098061hybridization-mixing atomic orbitals to from special orbitals for bonding -individual atom (normally center atom in a molecule) does this -based on how many e- areas (lone pair groups, bonds)are around the atom; for ea. e- area, one orbital added -ex-->O in H₂O has 4 e- areas, so: sp³ C in CO₂ has 2 e- areas, so: sp P in PCl₅ has 5 e- areas, so: sp³d47
6303098062trigonal planar-3 e- groups -120° apart48
6303098063bent-2 e- groups -normally in the molecular shape b/c two lone pairs were lost from tetrahedral (or one pair from trigonal planar)49
6303098064tetrahedral-4 e- groups -109° apart50
6303098065trigonal pyramidal-3 e- groups -normally in the molecular shape b/c one lone pair from the tetrahedral was lost51
6303098066molecular shape-the electronic shape minus the lone pairs52
6303098067electronic shape-all e- counted; lone pairs counted like bonds53
6303098068trigonal bipyramidal-5 e- groups -120° (in triangle), 90° (up/down elements) -when lone pairs are removed for molecular, they are removed from the trigonal planar part b/c bond angle is larger--> can become see-saw, T-shaped, or linear54
6303098069octahedral-6 e- groups -90° -when lone pairs removed shapes are: square pyramid, square planar55
6303098070phase and IMF's-molecules w/ weak IMF's tend to be gases at room temperature -molecules w/ strong IMF's tend to be solids @ room temp.56
6303098071Ideal Gas EquationPV = nRT -P = pressure in atm -V = volume in liters -n = moles -R = .0821 -T = temperature in Kelvin57
6303098072Kinetic Molecular Theory1. volume of gas particles = 0 (b/c they're so small compared w/ distance between them) 2. Pressure is caused by collisions of particles with walls 3. Particles don't attract/repel each other 4. Avg. kinetic energy = 1.5R/T58
6303098073Variation of Ideal Gas Equation-@ constant temp: PV = PV -@ constant pressure: V/T = V/T -constant temp/pressure: V/n = V/n (n = # of moles)59
6303098074Dalton's Law-total pressure of a mixture of gases is the sum of all the partial pressures of gases60
6303098075Partial Pressure= (total pressure)(moles of gas A/ total moles of gas)61
6303098076Deviation of Ideal Gas-happens at low temp. or high pressure -this is b/c the volume of gas molecules become relevant, raising the volume and gas molecules can start attracting each other, lowering the pressure62
6303098077Molaritymoles of solute / liters of solution63
6303098078mole fractionmoles of substance A / total moles of solution64
6303098079synthesis reaction-simple compounds combined to form one, more complex, compound65
6303098080decomposition reaction-a single compound is split into 2+ compounds66
6303098081acid-base reaction-an acid reacts with a base to form water and a salt -ex→ HCl + NaOH → H₂O + NaCl67
6303098082oxidation-reduction (redox) reaction-oxidation states of some participating molecules -ex→ Cu²⁺ + 2e- → Cu68
6303098083precipitation reaction-2 aqueous solutions mix and an insoluble salt is created69
6303098084net ionic equation-spectator ions that stay aqueous on both the reactants and products side are not included70
6303098085solubility rules-compounds w/ an alkali metal are soluble -compounds w/ an NH₄⁺ are soluble -compounds w/ an NO₃⁻ are soluble71
6303098086limiting reactant problems1. pick one product, and see how many moles of that product each reactant would make 2. the reactant making the least amount of the product is the limiting reactant72
6303098087enthalpy change (∆H)-= H(reactants) - H(products) -energy is released when bonds are formed -energy is absorbed when bonds are broken -positive = endothermic; negative = exothermic73
6303098088energy diagrams-displays the reaction as a graph74
6303098089catalyst-lowers the activation energy by displaying an alternate path -in a rxn mechanism, it would be in reactants of 1st step and products of last step, but not in overall equation75
6303098090oxidation states--covalent compound-if they are identical atoms, the e- are split equally (o.s. of 0) -if they are different atoms, the e- are given to the atom with stronger attraction to e-76
6303098091oxidation states--ionic compounds-same as the ion charge77
6303098092oxidation states-of a compound, they must = 0 or the charge of the ion -help keep track of e- in redox rxns78
6303098093an atom is oxidized-when the atom's o.s. decreases as it gains e-79
6303098094an atom is reduced-when the atom's o.s. increases as it loses e-80
6303098095oxidation states--special cases-Fluorine→o.s. of -1 -Oxygen→o.s. of -2 in covalent; -1 in peroxides; +2 in OF₂ -Hydrogen→o.s. of +1 in covalent w/ nonmetals81
6303098096oxidation states--atom/one element-is always 0 -ex→F₂, Hg82
6303098097rate lawrate law = k[A]ⁿ[B]∧m[C]∧p -[x] = concentration of reactant -n/m/p = 0,1, or 2 -k = rate constant -greater the order, the more that reactant affects the rate83
6303098098determining order (rate law)-[A1] times x equals [A2]= rate1 times y equals rate2 -if x⁰ = 1 = y, zero order -if x¹ = y, first order -if x² = y, second order84
6303098099first order rate law-ln[A] = -kt + ln[A]₀ -straight line when time v. ln(concentration); slope of this line is -k85
6303098100second order rate law-1/[A] = kt + 1/[A]₀ -straight line when time v. 1/concentration; slope of k86
6303098101zero order rate law-[A] = -kt + [A]₀ -slope of graph = -k -straight line when time v. concentration87
6303098102finding half-life1. take the rate law equation (either 0, 1, or 2 order) and plug 1 in for [A₀] and 1/2 in for [A] 2. solve for t to find half-life Hint: for 1st order it's .693/k88
6303098103collision theorymolecules must collide with correct orientation and enough energy in order to react89
6303098104reaction rate increases......as concentration of reactants increases -as temperature increases -as surface area increases -as volume decreases -when a catalyst is added90
6303098105Beer's LawA = abc -A = absorbance -a = molar absorptivity constant -b = path length (how far light travels thru solution) -c = concentration of soln. -used w/ a spectrophotometer to find absorbency and concentration91
6303098106reaction mechanism-series of individual chemical (elementary) steps by which an overall chemical reaction occurs92
6303098107intermediate-species that is formed in one elementary step and consumed in the next so it is NOT a product or reaction in the overall equation93
6303098108rate determining stepslowest step; the rate law = those reactants' molarity raised to the power of their coefficient94
6303098109heat-total energy due to molecular motions in a substance (not the same as temperature)95
6303098110temperature-measurement of the average kinetic energy of a substance (not the same as heat)96
6303098111types of energy transfer-heat (energy goes from a warm object to a cold one) -work (substance is stirred, raising its energy)97
6303098112first law of thermodynamics-energy of the universe is constant -energy can't be created or destroyed, only converted98
6303098113second law of thermodynamics-if a reaction happens spontaneously (on its own) in one direction, it won't happen spontaneously in the reverse direction -entropy of universe increases during spontaneous reaction99
6303098114state functions-enthalpy (H), entropy (S), and free-energy (G) change -don't depend on the actual process of the reaction -depend only the initial and final states100
6303098115standard state conditions-are true when you see a °, like H° -include: gases @ 1atm, pure solids/liquids. 1M substances, element @ normal states has energy of formation (∆H°ƒ) of 0101
6303098116Heat of formation, ∆H°-change in energy when 1 mole of a compound is formed from pure elements -exothermic → H is negative -endothermic → H is positive -pure element → H is zero = ∑∆H°ƒ reactants- ∑∆H°ƒ products102
6303098117bond energy-energy required to break a bond -always endothermic and positive -∆H° = ∑ bond energy of broken bonds - ∑ bond energy of formed bonds103
6303098118Hess's Law-if a reaction happens in multiple steps, you can add the ∆H values of the steps together -if you flip the equation, flip the sign of the ∆H -if you multiply/divide the equation, multiply/divide the ∆H104
6303098119vapor pressure-pressure of the molecules as they escape from the surface -water boils when vapor pressure = atmospheric pressure105
6303098120heat of fusion-energy that must be put into a solid to melt it106
6303098121heat of vaporization-energy needed to turn a liquid into a gas107
6303098122phase diagram-in water (when solid is less dense than liquid) line between solid/liquid slopes downward108
6303098123heat capacity-measure of how much the temperature of an object is raised when is absorbs heat -large = absorbs a lot w/o changing temp.109
6303098124specific heat-amount of heat needed to raise 1g of a substance 1°C110
6303098125heat added/ calorimetry equationq = mc∆T -q - heat added (J or cal) -m - mass -c - specific heat -∆T - temperature change111
6303098126entropy (∆S)-measure of the randomness -entropy of solid < liquid < gas -two moles have more entropy than one112
6303098127Gibbs free energy (∆G)-measure of whether a process will proceed w/o outside energy -∆G positive→ won't happen -∆G negative → will happen -∆G = 0 → equilibrium = ∑∆G°ƒ products - ∑∆G°ƒ reactants113
6303098128equilibriumwhen the rate of the forward reaction is equal to the rate of the reverse reaction114
6303098129law of mass action (Keq)-for aA + bB ⇌ cC + dD, Keq = [C]^c [D]^d / [A]^a [B]^b -only gases and aqueous substances are included115
6303098130What does the Keq mean?-if it's large, then products are favored at equilibrium -if it's small, then reactants are favored at equilibrium116
6303098131Different K's-Kc → constant for molar concentrations -Kp → constant for partial pressures -Ksp → solubility product -Ka → acid constant for weak acids -Kb → base constant for weak bases -Kw → water ionization117
6303098132Le Chatelier's Law-whenever stress is placed on a reaction @ equilibrium, the equilibrium will shift to relieve the stress -stress can be concentration, temp., pressure, volume118
6303098133Le Chatelier's Law--Concentration-if the concentration increases equilibrium will shift away from that substance -if the concentration decreases equilibrium will shift towards that substance119
6303098134Le Chatelier's Law--Volume-if the volume decreases (increases) then equilibrium will shift toward the side with less (more) moles of gas molecules120
6303098135Le Chatelier's Law--Temperature-exothermic → heat is a product -endothermic → heat is a reactant -treat like concentration problem121
6303098136Le Chatelier's Law--Pressure-if the pressure decreases (increases) then equilibrium will shift toward the side with more (less) molecules of gas -if a inert gas is added, there will be no change122
6303098137reaction quotient, Q-determined just like equilibrium constant, K, but using initial conditions123
6303098138comparing K and Q-if K > Q, then more products need to be made -if Q > K, then more reactants are needed -if Q = K, then the reaction is at equilibrium124
6303098139K in a multistep reaction-if reactions are added together, then their K's must be multiplied125
6303098140Ksp-measure of how much a salt disassociates in a solution -higher the Ksp, more soluble the salt126
6303098141Arrhenius Acid-Base Definition-acid → substance that produces H⁺ ions -base → substance that produces OH⁻ ions127
6303098142Bronsted-Lowry Acid-Base Definition-acid → proton donor -base → proton acceptor128
6303098143conjugate base-used to be part of an acid; now acts as a base because it will accept an H⁺ -ex → Cl⁻ from HCl129
6303098144conjugate acid-used to be part of an base; now acts as a acid because it will donate an H⁺ -ex → NH₄⁺ from NH₃130
6303098145how to find pHpH = -log[H⁺] pOH = -log[OH⁻] pH + pOH = 14131
6303098146weak acid-acid that will only dissociate a little when placed in water -Ka = [A⁻][H⁺]/[HA] -greater the Ka, more dissociation, stronger the acid132
6303098147weak base / Kb =-base that will only dissociate a little when placed in water -Kb = [HA][OH⁻]/[B] -greater the Kb, more dissociation, stronger the base133
6303098148strong acid-completely dissociates in water -HCl, HBr, HI, HClO₄, HNO₃, H₂SO₄134
6303098149strong base-completely dissociates in water -alkali metals and Ba, Sr -LiOH, NaOH, KOH, Ba(OH)₂, Sr(OH)₂135
6303098150Kw-water dissociation constant = 1.0 x 10⁻¹⁴ = [H⁺][OH⁻] = KaKb136
6303098151Henderson-Hasselbalch Equation-use for buffers; when you have a weak acid and conjugate base or weak base and conjugate acid pH = -log(Ka) + log([base] / [acid])137
6303098152buffer-consists of weak acid and conjugate base OR weak base and conjugate acid pH = pKa + log([base]/[acid])138
6303098153amphoteric-substance that can act as a base or an acid139
6303098154polyprotic acids-have more than one H⁺ -ex → H₂SO₄, H₃PO₄ -will give off one H⁺ at a time; each successive acid is weaker140
6303098155titration curve--SA w/ SB-starts near 1, ends near 14 -equivalence point at 7141
6303098156equivalence point-point in a titration where H⁺ and OH⁻ concentrations are equal142
6303098157titration curve--WA w/ SB-starts near 3, ends near 14 -equivalence point above 7143
6303098158titration curve--polyprotic acid-has as many equivalence points as it does H⁺'s -equivalence points are equidistant from each other144
6303098159titration lab-rinse buret with solution to be used -if it's rinsed with water, the solution will be diluted and the volume of the titrant will be too much145
6303098160massing objects-don't mass hot objects; they don't measure correctly -don't weigh stuff directly on a scale146
6303098161what is a galvanic cell-a redox reaction is separating into the oxidation and reduction parts to generate current147
6303098162anode-electrode where oxidation happens in a galvanic cell148
6303098163cathode-electrode where reduction happens in a galvanic cell149
6303098164parts of a galvanic cell-salt bridge--> maintains neutrailty; ions flow into anode side -wire--> e- move from anode to cathode -solid and aqueous ions--> same type are together in a container150
6303098165galvanic cell equation-take both half-reactions and decide to 'flip' one of them to make in an oxidation reaction -'flip' the one that, when its E° turns negative, adding the E°'s together won't make a negative number -note: current and work can only be done if E° is positive151
6303098166electrolytic cell-outside energy source is used to force a non-spontaneous reaction152
6303098167electroplating conversions1. know that 1 amp = 1 C / sec and that there are 96,500 C / mol e- 2. starts with the time given, convert to seconds, then C, then mol e-, then the moles of e- in problem, and then moles of the metal (or vice verse) note: moles of the metal is found when making/canceling out the equation153
6303098168thermodynamics-says whether a rxn will occur; not how fast it will ocurr154
6303098169entropy-S° -measures the randomness/disorder -reactions will favor increases in entropy - (more entropy) gas, aqueous, liquid, solid (less entropy)155
6303098170Gibbs Free Energy, G-if ∆G is negative, rxn is thermodynamically favored (spontaneous) -if ∆G is positive, rxn is thermodynamically unfavored (NOT spontaneous) -if ∆G = 0, rxn is at equilibrium -∆G° = ∑(n(G° product)) - ∑(n(G° reactant)) (same formula for ∆S, ∆H)156
6303098171∆G° = ∆H° - T∆S°-make sure units are right! 1 kJ = 1000 J (just add 3 zeros) - -H, +S = -G (spontaneous) - -H, -S = -G (@ low temp.), +G (@ high temp.) - +H, +S = -G (@ high temp.), -G (@ low temp.) - +H, -S = +G (not spontaneous)157
6303098172∆G° = -nFE°-n = number of moles of e- -F = Farday's constant (96,500 C / mol e-) -E = energy potential (1V = 1 J / C)158
6303098173photon-increase the energy of the photon by increasing the frequency159
6303098174electromagnetic radiation spectrum-listing in increasing frequency and decreasing wavelength -radio / infrared / visible / UV / x-ray / gamma160
6303098175sublimationsolid to gas161
6303098176Boyle's LawP₁V₁=P₂V₂162
6303098177effective nuclear charge-as this increases, ionization / binding energy increases -nucleus' pull on electrons, partially weakened by shielding effect163
6303098178chromatography-paper is somewhat polar, so if your solvent is non-polar the polar molecules will be low on the paper while the non-polar molecules will travel with the solvent to the top164
6303098179pKathe pH that is halfway to the equivalence point165
6303098180[H⁺] == 10^-pH166

Need Help?

We hope your visit has been a productive one. If you're having any problems, or would like to give some feedback, we'd love to hear from you.

For general help, questions, and suggestions, try our dedicated support forums.

If you need to contact the Course-Notes.Org web experience team, please use our contact form.

Need Notes?

While we strive to provide the most comprehensive notes for as many high school textbooks as possible, there are certainly going to be some that we miss. Drop us a note and let us know which textbooks you need. Be sure to include which edition of the textbook you are using! If we see enough demand, we'll do whatever we can to get those notes up on the site for you!