Terms : Hide Images
| 13913662527 | isotope | element with a different number of neutrons | 0 | |
| 13913662528 | mass spectrometry | mass of various isotopic elements to create a mass spectrum graph | 1 | |
| 13913662529 | avogadros number | 6.022 E23 | 2 | |
| 13913662530 | ? L/mol | 22.4 L | 3 | |
| 13913662531 | empirical formula | simplest ratio of the molecules making up a compound | 4 | |
| 13913662532 | molecular formula | actual formula for a substance | 5 | |
| 13913662533 | coulombs law | the amount of energy that an electron has depends on its distance from the nucleus of an atom; e=k(q1*q20)/r | 6 | |
| 13913662534 | ionization energy | amount of energy necessary to remove electrons from an atom (electromagnetic energy exceeds binding energy) | 7 | |
| 13913662535 | shielding electrons | electrons between a valence electron and the nucleus that decreases the attraction between the nucleus and the valence electron | 8 | |
| 13913662536 | periodic trend: left to right | periodic trend: atomic radius decreases; protons are added to the nucleus so valence electrons are more strongly attracted ionization energy increases (protons are added to the nucleus) | 9 | |
| 13913662537 | periodic trend: down a group | periodic trend: atomic radius increases; shells of electrons are added which shield the more distant shells and valence e- get farther away ionization energy decreases (shells of e- added, each inner shell shields more and reduces the pull on valence e- so they are easier to remove) | 10 | |
| 13913662538 | ionic bond | bond between metal and nonmetal; electrons are NOT shared: the cation gives an e- up to the anion |  | 11 |
| 13913662539 | metallic bonding | bond between two metals; sea of electrons that make metals such good conductors; delocalized structure allows for malleability and ductility | 12 | |
| 13913662540 | interstitial alloy | metal atoms with vastly different radii combine; ex. steel |  | 13 |
| 13913662541 | substitutional alloy | metal atoms with similar radii combine; ex. brass |  | 14 |
| 13913662542 | covalent bonds | bond in which two atoms share electrons; each atom counts the e- as a part of its valence shell |  | 15 |
| 13913662543 | single bonds | one sigma bond, one e- pair; longest bond, least energy | 16 | |
| 13913662544 | double bonds | one sigma bond, one pi bond; two e- pairs | 17 | |
| 13913662545 | triple bonds | one sigma bond, two pi bonds; 3 e- pairs; shortest bond, most energy | 18 | |
| 13913662546 | network covalent bonds | lattice of covalent bonds; network solid (acts similar to one molecule); very hard, high melting/boiling points; poor conductors | 19 | |
| 13913662547 | the common network solids | SiO2, | 20 | |
| 13913662548 | doping | the addition of an impurity to an existing lattice | 21 | |
| 13913662549 | p-doping | create a hole (positively charged) that draws electrons through the substance (add a substance with one LESS valence e-) i.e. si + al | 22 | |
| 13913662550 | n-doping | add a substance with one MORE valence e- which leaves a free e- to travel freely i.e. si + p | 23 | |
| 13913662551 | polarity | exists when a molecule has a clustering of negative charge on one side due to unequal sharing of electrons (e- are pulled to the more electronegative side); creates dipoles in molecules | 24 | |
| 13913662552 | dipole moment | the measurement of the polarity of a molecule; the unit of measurement is a debye (D) |  | 25 |
| 13913662553 | more polar molecule.... | .... larger dipole moment | 26 | |
| 13913662554 | intermolecular forces (IMFs) | forces that exist between molecules in a covalently bonded substance; not bonds | 27 | |
| 13913662555 | dipole-dipole forces | the positive end of one polar molecule is attracted to the negative end of another molecule; relatively weak attraction force |  | 28 |
| 13913662556 | hydrogen bonding | strong IMF between two moelcules; F, O, N; have higher melting and boiling points than molecules with other IMFs |  | 29 |
| 13913662557 | london dispersion forces | IMFs that occur between all molecules; occur because of the random motions of electrons on atoms within molecules to create instantaneous polarities; molecules with more e- will have greater _________________ forces | 30 | |
| 13913662558 | substances with only london dispersion forces usually... | ... are gases at room temp, and boil/melt at extremely low temps | 31 | |
| 13913662559 | melting & boiling points of a covalent substance is almost always _____________ than that of ionic substances | lower | 32 | |
| 13913662560 | vapor pressure | the pressure exerted by a vapor over a liquid | 33 | |
| 13913662561 | resonance structures | structures that occur when it is possible to draw two or more valid lewis electron dot diagrams that have the same number of electron pairs for a molecule or ion | 34 | |
| 13913662562 | formal charge | used to find which structure is most likely to occur; valence - assigned | 35 | |
| 13913662563 | linear geometry | sp hybridization 0 lone pairs ex. BeCl2 & CO2 |  | 36 |
| 13913662564 | trigonal planar geometry | sp2 hybridization bond angles 120 0 lone pairs: trigonal planar (three bonds) 1 lone pair: bent (two bonds) |  | 37 |
| 13913662565 | tetrahedral geometry | 4 e- pairs, sp3 hybridization angles 109.5 0 lone pairs: tetrahedral (four bonds) [CH4, NH4+, ClO4-, SO4 2-, PO4 3-] 1 lone pair: trigonal pyramidal (3 bonds) [NH3, PCl3, SO3 2-] 2 lone pairs: bent (2 bonds) [H2O, OF2, NH2-] |  | 38 |
| 13913662566 | trigonal bipyramidal geometry | 5 e- pairs, sp4 hybridization 0 lone pairs: trigonal bipyramidal (5 bonds) [PCl5, PF5] 1 lone pair: seesaw (4 bonds) [SF4, IF4+] 2 lone pairs: t-shaped (3 bonds) [ClF3, ICl3] 3 lone pairs: linear (2 bonds) [XeF2, I3-] |  | 39 |
| 13913662567 | octahedral geometry | 6 e- pairs, sp5 hybridization 0 lone pairs: octahedral (6 bonds) [SF6] 1 lone pair: square pyramidal (5 bonds) [BrF5, IF5] 2 lone pairs: square planar (4 bonds) [XeF4] |  | 40 |
| 13913662568 | maxwell-boltzmann diagrams | shows the range of velocities for molecules of a gas | 41 | |
| 13913662569 | effusion | the rate at which a gas will escape from a container through microscopic holes in the surface of the container | 42 | |
| 13913662570 | mole fraction | moles of substance/total moles in solution | 43 | |
| 13913662571 | dissociation | when ionic substances break up into ions into solution | 44 | |
| 13913662572 | electrolytes | free ions in solution that conduct electricity | 45 | |
| 13913662573 | paper chromatography | the separation of a mixture by passing it through a medium in which the components of the solution move at different rates | 46 | |
| 13913662574 | retention factor | stronger the attraction between the solute and the solvent front is, the larger the Rf value will be |  | 47 |
| 13913662575 | column chromatography | a column is packed with stationary substance, then the solution to be separated (analyte) is injected into the column where it adheres to the stationary phase, then the eluent solution is injected into the column. as the eluent solution passes through the stationary phase the analyte molecules will be attracted to it with varying degrees of strength based on polarity | 48 | |
| 13913662576 | distillation | the process that separates the substances in a solution based on their boiling points |  | 49 |
| 13913662577 | precipitation reaction | a reaction in which an insoluble substance (salt) forms and separates from the solution | 50 | |
| 13913662578 | net ionic equation | an equation for a reaction in solution showing only those particles that are directly involved in the chemical change |  | 51 |
| 13913662579 | limiting reactant | the substance that controls the quantity of product that can form in a chemical reaction; moles of each reactant divided by moles used in reaction | 52 | |
| 13913662580 | gravimetric analysis | a type of quantitative analysis in which the amount of a species in a material is determined by converting the species to a precipitate that can be isolated completely and weighed | 53 | |
| 13913662581 | when bonds are formed | ...energy is released | 54 | |
| 13913662582 | when bonds are broken | ...energy is absorbed | 55 | |
| 13913662583 | exothermic | products have stronger bonds than the reactants; heat is released, - ΔH | 56 | |
| 13913662584 | endothermic | reactants have stronger bonds than the products; heat is absorbed, + ΔH | 57 | |
| 13913662585 | activation energy | the minimum amount of energy required to start a chemical reaction | 58 | |
| 13913662586 | catalyst | substance that speeds up a reaction by reducing the activation energy required by the reaction; provides an alternate reaction pathway; no effect on equilibrium conditions | 59 | |
| 13913662587 | oxidation number: H | +1 | 60 | |
| 13913662588 | entropy | ΔS; a measure of the randomness or disorder of the system | 61 | |
| 13913662589 | enthalpy | ΔH; heat of a system at constant pressure | 62 | |
| 13913662590 | Gibbs free-energy | ΔG; a measure of whether or not a process will proceed without the input of outside energy ∆G=∆H-T∆S (T in degrees Kelvin) when ΔG=0, the reaction is at equilibrium | 63 | |
| 13913662591 | spontaneous | thermodynamically favored; -ΔG | 64 | |
| 13913662592 | nonspontaneous | thermodynamically unfavored; +ΔG | 65 | |
| 13913662593 | Arrhenius acids | a substance that ionizes in water and produces hydrogen ions | 66 | |
| 13913662594 | Arrhenius bases | a substance that ionizes in water and produces hydroxide ions | 67 | |
| 13913662595 | Brønsted-Lowry acids | a substance that is capable of donating a proton | 68 | |
| 13913662596 | Brønsted-Lowry bases | a substance that is capable of accepting a proton | 69 | |
| 13913662597 | pH | -log [H+] | 70 | |
| 13913662598 | pOH | -log [OH-] | 71 | |
| 13913662599 | pKa | -log [Ka] | 72 | |
| 13913662600 | pKb | -log [Kb] | 73 | |
| 13913662601 | amphoteric | a substance that can act as both an acid and a base; ex. H2O | 74 | |
| 13913662602 | strong acids | dissociate completely in water; reaction goes to completion and never reaches equilibrium | 75 | |
| 13913662603 | weak acid | most of the acid molecules remain in solution and very few dissociate | 76 | |
| 13913662604 | percent dissociation | the ratio of the amount of a substance that is dissociated at equilibrium to the initial concentration of the substance in a solution, multiplied by 100 | 77 | |
| 13913662605 | oxoacids | acids that contain oxygen; the more oxygens, the stronger the acid | 78 | |
| 13913662606 | polyprotic acids | acids that can donate more than one H+ |  | 79 |
| 13913662607 | Kw | 1.0x10^-14 | 80 | |
| 13913662608 | henderson hasselbach | pH = pKa + log([A-]/[HA]) | 81 | |
| 13913662609 | buffers | weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH | 82 |
