{ "source": "https://peabody.kids/flashcards/tp-ap-chemistry", "id": "tp-ap-chemistry", "title": "AP Chemistry Key Terms", "category": "test-prep", "subject": "AP Chemistry", "levels": [ "9-12", "college" ], "description": "Vocabulary and relationships from atomic structure to equilibrium, kinetics and thermodynamics.", "tags": [ "ap", "chemistry" ], "frontLabel": "Term", "backLabel": "Meaning", "cards": [ [ "Mole", "6.022 x 10^23 particles; the chemist's counting unit" ], [ "Avogadro's number", "6.022 x 10^23 per mole" ], [ "Molar mass", "Mass in grams of one mole of a substance" ], [ "Empirical formula", "The simplest whole-number ratio of atoms" ], [ "Molecular formula", "The actual number of each atom in a molecule" ], [ "Percent composition", "Mass percent of each element in a compound" ], [ "Limiting reactant", "The reactant that runs out first and caps the product" ], [ "Theoretical yield", "The maximum product predicted by stoichiometry" ], [ "Percent yield", "(actual yield / theoretical yield) x 100" ], [ "Molarity", "Moles of solute per liter of solution" ], [ "Dilution equation", "M1V1 = M2V2" ], [ "Isotope", "Atoms of one element with different numbers of neutrons" ], [ "Average atomic mass", "Weighted average of an element's isotopes" ], [ "Mass spectrometry", "Measures isotope masses and abundances" ], [ "Photoelectron spectroscopy", "Measures energies needed to remove electrons from atoms" ], [ "Electron configuration", "Arrangement of electrons in orbitals" ], [ "Aufbau principle", "Fill lowest-energy orbitals first" ], [ "Pauli exclusion principle", "No two electrons in an atom share all four quantum numbers" ], [ "Hund's rule", "Fill degenerate orbitals singly before pairing" ], [ "Valence electrons", "Outer-shell electrons involved in bonding" ], [ "Effective nuclear charge", "Net pull felt by outer electrons" ], [ "Atomic radius trend", "Decreases across a period, increases down a group" ], [ "Ionization energy trend", "Generally increases across a period, decreases down a group" ], [ "Electronegativity", "An atom's pull on shared electrons in a bond" ], [ "Coulomb's law", "Force depends on charges and decreases with distance squared" ], [ "Ionic bond", "Attraction between oppositely charged ions" ], [ "Covalent bond", "A shared pair of electrons" ], [ "Metallic bond", "Positive ions in a sea of delocalized electrons" ], [ "Lattice energy", "Energy released when gaseous ions form an ionic solid" ], [ "Bond order", "Number of bonding pairs between two atoms" ], [ "Bond length trend", "Higher bond order means shorter, stronger bonds" ], [ "Lewis structure", "A diagram of valence electrons and bonds" ], [ "Formal charge", "Valence electrons minus nonbonding electrons minus half the bonding electrons" ], [ "Resonance", "Multiple valid Lewis structures for one species" ], [ "VSEPR theory", "Electron groups arrange to minimize repulsion" ], [ "Linear geometry", "Two electron groups; 180 degrees" ], [ "Trigonal planar", "Three electron groups; 120 degrees" ], [ "Tetrahedral", "Four electron groups; 109.5 degrees" ], [ "Hybridization sp3", "Four electron groups, tetrahedral" ], [ "Sigma bond", "Head-on overlap of orbitals" ], [ "Pi bond", "Side-by-side overlap of p orbitals" ], [ "Polar bond", "A bond with unequal sharing" ], [ "London dispersion forces", "Weak attractions from temporary dipoles; present in all molecules" ], [ "Dipole-dipole force", "Attraction between polar molecules" ], [ "Hydrogen bonding", "Strong dipole attraction involving H bonded to N, O or F" ], [ "Ideal gas law", "PV = nRT" ], [ "Combined gas law", "P1V1/T1 = P2V2/T2" ], [ "Dalton's law", "Total pressure is the sum of partial pressures" ], [ "Kinetic molecular theory", "Gas particles move randomly with energy proportional to temperature" ], [ "Graham's law", "Lighter gases effuse faster" ], [ "Real gas deviation", "Gases act least ideally at high pressure and low temperature" ], [ "Solute", "The substance dissolved" ], [ "Solvent", "The substance doing the dissolving" ], [ "Electrolyte", "A substance that forms ions in water and conducts" ], [ "Net ionic equation", "Shows only the species that change, omitting spectators" ], [ "Spectator ion", "An ion unchanged by a reaction" ], [ "Precipitate", "An insoluble solid formed in solution" ], [ "Beer-Lambert law", "Absorbance is proportional to concentration: A = abc" ], [ "Oxidation", "Loss of electrons" ], [ "Reduction", "Gain of electrons" ], [ "Oxidizing agent", "The species that is reduced" ], [ "Reducing agent", "The species that is oxidized" ], [ "Rate law", "Equation relating reaction rate to concentrations" ], [ "Reaction order", "The exponent of a reactant in the rate law" ], [ "Rate constant", "The proportionality constant k in the rate law" ], [ "First-order half-life", "ln 2 / k; independent of concentration" ], [ "Collision theory", "Reactions need collisions with enough energy and proper orientation" ], [ "Activation energy", "Minimum energy for a successful collision" ], [ "Catalyst", "Speeds a reaction by giving a lower-energy path; not consumed" ], [ "Rate-determining step", "The slowest step in a mechanism" ], [ "Reaction intermediate", "A species made then used up within a mechanism" ], [ "Arrhenius equation", "Relates rate constant to temperature and activation energy" ], [ "Endothermic", "Absorbs heat; positive delta H" ], [ "Exothermic", "Releases heat; negative delta H" ], [ "Specific heat", "Energy needed to raise 1 g of a substance by 1 degree C" ], [ "Calorimetry", "Measuring heat flow, q = mc delta T" ], [ "Enthalpy of formation", "Heat change when 1 mol forms from elements in standard states" ], [ "Hess's law", "Total enthalpy change is the sum of steps" ], [ "Bond enthalpy", "Energy needed to break a bond" ], [ "Entropy", "A measure of disorder or energy dispersal" ], [ "Gibbs free energy", "Delta G = delta H - T delta S; negative means spontaneous" ], [ "Standard state", "Reference conditions for thermodynamic data, 1 bar" ], [ "Equilibrium", "Forward and reverse rates are equal" ], [ "Equilibrium constant K", "Ratio of products to reactants at equilibrium" ], [ "Reaction quotient Q", "Same ratio at any moment; compare with K to predict direction" ], [ "Le Chatelier's principle", "A system at equilibrium shifts to counteract a stress" ], [ "Ksp", "Solubility product constant for a slightly soluble salt" ], [ "Common ion effect", "A shared ion lowers solubility" ], [ "Arrhenius acid", "Produces H+ in water" ], [ "Bronsted-Lowry acid", "A proton donor" ], [ "Lewis acid", "An electron pair acceptor" ], [ "Conjugate acid-base pair", "Two species differing by one proton" ], [ "pH", "Negative log of hydrogen ion concentration" ], [ "Kw", "Ion product of water, 1.0 x 10^-14 at 25 degrees C" ], [ "Strong acid", "Dissociates completely in water" ], [ "Buffer", "A solution that resists pH change; weak acid plus its conjugate base" ], [ "Henderson-Hasselbalch equation", "pH = pKa + log([A-]/[HA])" ], [ "Titration equivalence point", "Moles of acid equal moles of base" ], [ "Indicator", "A dye that changes color near the endpoint" ], [ "Electrochemical cell", "Converts chemical energy to electrical energy or the reverse" ], [ "Anode", "Electrode where oxidation occurs" ], [ "Cathode", "Electrode where reduction occurs" ], [ "Standard cell potential", "E-cell = E-cathode minus E-anode" ], [ "Salt bridge", "Allows ion flow to keep solutions neutral" ], [ "Electrolysis", "Using electricity to drive a nonspontaneous reaction" ], [ "Faraday's constant", "About 96,485 coulombs per mole of electrons" ] ] }