Chemistry Final Flashcard
Unlock all answers in this set
Unlock answersquestion
| Ionization Energy |
answer
| the energy required to remove an electron from a gaseous atom or ion trend: increases across period and up group (highest=He) |
question
| Electron Affinity |
answer
| the energy change associated with the addition of an electron to a gaseous atom trend: becomes more negative across period and up group (changes down group are small and numerous exceptions) |
question
| Atomic Radius |
answer
| half the distance between the nuclei in a molecule consisting of two identical atoms trend: decrease from left to right and increases down group |
question
| Mixture vs. Pure Substance |
answer
| mixture: variable composition (homogeneous (solution) or heterogeneous) pure substance: constant composition (element or compound) |
question
| Law of Definite Proportion |
answer
| A given compound always contains exactly the same proportion of elements by mass |
question
| Law of Multiple Proportions |
answer
| When two elements form a series of compounds the ratios of the masses of the second element that combine with 1 gram of the first element can always be reduced to small whole numbers |
question
| Dalton's Atomic Theory |
answer
| 1. each element is made up of tiny particles called atoms 2. the atoms of a given element are identical, the atoms of different elements are different in some fundamental way or ways 3. chemical compounds are formed when atoms of different elements combine with each other. a given compound always has the same relative numbers and types of atoms 4. chemical reactions involve reorganization of the atoms, the atoms themselves are not changed |
question
| Empirical Formula vs. Molecular Formula |
answer
| empirical: simplest whole number ratio of the atoms in a compound molecular: exact formula of molecule |
question
| Strong Electrolytes vs. Weak Electrolytes vs. Nonelectrolytes |
answer
| strong: completely ionize weak: partially ionize non: don't produce any ions |
question
| Molarity |
answer
| moles solute/Liters solution |
question
| Solubility Rules |
answer
| 1. nitrate (NO3-) soluble 2. alkali metals and ammonium (NH4+) soluble 3. chloride, bromide, iodide soluble (except Ag+, Pb2+, Hg2 2+) 4. sulfate (SO4 2-) soluble (except Ba, Pb, Hg2, Ca) 5. hydroxides (OH-) slightly soluble (except NaOH, KOH) 6. sulfide (S2-), carbonate (CO3 2-), chromate (CrO4 2-), and phosphate (PO4 3-) slightly soluble |
question
| Types of Chemical Equations |
answer
| formula equation: reactants and products in undissociated form complete ionic equation: all strong electrolytes shown as ions net ionic equation: spectator ions eliminated |
question
| Bronstead Acids and Bases |
answer
| Acid: proton donator Base: proton acceptor |
question
| Arrenhius Acids and Bases |
answer
| Acid: produces H+ ions (H3O+) in water Bases: produces OH- ions in water |
question
| Oxidation-Reduction Reactions (Redox) |
answer
| electrons are transferred oxidation: increase in oxidation state, loss of electrons reduction: decrease, gain oxidizing agent: electron acceptor reducing agent: electron donator |
question
| Gas Laws |
answer
Boyle: PV=k Charles: V=bT Avogadro: V=an Ideal Gas Law: PV=nRT molar mass=(dRT)/P Dalton's Law of Partial Pressures: Ptotal=P1+P2+P3...
|
question
| Kinetic Molecular Theory Gases |
answer
| 1. volume is negligible 2. constant random motion 3. no repulsive or attractive forces 4. average kinetic energy in directly proportional to Kelvin temp 5. collisions with each other and container are elastic followed at low pressure and high temperatures |
question
| Endothermic vs. Exothermic |
answer
| Exothermic: potential energy stored in bonds is converted to thermal energy, reactants have higher potential energy, bonds in products are stronger than reactants, more energy is released when new bonds in products are formed than is consumed to break bonds in reactants Endothermic: energy flows into system as heat increases potential energy, products have higher potential energy and weaker bonds |
question
| Thermodynamic Law-thingies |
answer
| sum of kinetic and potential energies ?E=q + w q: + energy added, - energy out w: + surroundings do work on system, - system does work on surroundings for gas work: w=-P?V |
question
| Enthalpy |
answer
| H=E + PV ?H=qp (at constant pressure) Hess's Law: enthalpy same regardless of steps from bond energies: ?H= ?n x D(bonds broken)-?n x D(bonds formed) |
question
| Calorimetry |
answer
| constant pressure: energy released by reaction=specific heat capacity of solution x mass of solution x increase in temperature= s x m x ?T constant volume: ?T x heat capacity of container |
question
| Standard Enthalpy of Formation |
answer
| change in enthalpy that accompanies the formation of one moles of a compound from its elements with all substances in their standard states Compound: gas at 1 atm, pure substance in condensed state is pure substance, solution is 1M Element: form at 1 atm and 25C ?Hf reaction=?Hf products - ?Hf reactants |
question
| Waves and craps |
answer
| ?v=c Ephoton=hv=(hc)/? de Broglie's Equation: ?=h/(mv) to calculate wavelength of particle |
question
| Quantum Numbers |
answer
| n: principle quantum number l: angular momentum, 0 to (n-1), shape 0=s, 1=p, 2=d, 3=f, 4=g ml: magnetic, -l to l, orientation ms: electron spin, -1/2 or 1/2 |
question
| Writing Electron Configurations Like a Boss |
answer
| 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d 7p number of orbitals per subshell: s=1, p=3, d=5, f=7, g=9 |
question
| Electronegativity |
answer
| the ability of an atom in a molecule to attract shared electrons to itself trend: fluorine highest, increases left to right, decreases down |
question
| Isoelectronic Ions |
answer
| same number of electrons more protons=smaller |
question
| Lattice Energy |
answer
| the change in energy that takes place when separated gaseous ions are packed together to for an ionic solid, negative, exothermic |
question
| Lewis Structures |
answer
| 1. Things can exceed the octet rule (I know, say whaaa?) like third row+ elements because of valence d orbitals 2. B and Be often have fewer than eight electrons, very reactive compounds C, N, O, F always assumed to obey octet rule Formal Charge: valence e- on free atom - valence e- assigned to atom in molecule, close to zero as possible and negative on most electronegative atom |
question
| VSEPR (valence shell electron-pair repulsion) Model |
answer
| 2 effective pairs: linear, 180 3: trigonal planar, 120 4: tetrahedral, 109.5 (3: trigonal pyramidal, 2: bent) 5: trigonal bipyramidal, 120 ; 90 (4: see-saw, 3: t-shaped, 2: linear) 6: octahedral, 90 (4: square planar) |
question
| Hybridization |
answer
| 2: sp, 3: sp2, 4: sp3, 5: dsp3, 6: d2sp3 sigma bonds: between atoms, pi bonds: above and below atoms, double bond: one sigma + one pi |
question
| Molecular Orbital Model |
answer
| bonding: lower in energy, antibonding: higher in energy bond order: (number of bonding e - number of antibonding e)/2, larger=stronger, larger bond energy, smaller length paramagnetism=unpaired, dimagnetism=paired B, C, N: sp mixing changes order O,F: no sp mixing |
question
| Localized Electron Model |
answer
| 1. Lewis structure 2. Arrangement of electron pairs according to VSEPR 3. Specify hybridization |
question
| Intermolecular Forces |
answer
dipole-dipole attraction: polar molecules hydrogen bonding: strong dipole-dipole forces, when hydrogen is bound to highly electronegative atom (N, O, F) london dispersion:induced dipole, polarizability: large atoms, more electrons higher electrostatic attraction: ionic compounds |
question
| Liquids |
answer
| surface tension: resistance of a liquid to an increase in its surface area, high IM forces=high surface tension capillary action: cohesive forces (IM between liquid molecules) and adhesive forces (between liquid and container, when container is polar) viscosity: resistance to flow |
question
| Solids |
answer
| crystalline (regular arrangement, lattice) vs. amorphous (disorder) types of crystalline: atomic, ionic, molecular X-ray diffraction according to n?=2dsin? |
question
| Unit Cells |
answer
| Simple Cubic: 1 net sphere, side= 2r Body-Centered Cubic: 2, side= r4/sqrt(3) Face-Centered Cubic: 4, side=rsqrt(8), 8 tetrahedral holes, 4 octahedral holes |
question
| Metals |
answer
| closest packing: aba=hexagonal closest packed (hcp) structure, abc= cubic closest packed (ccp) structure, face-centered |
question
| Vaporization |
answer
| endothermic enthalpy of vaporization: energy required to vaporize 1 mol liquid at 1 atm higher IM forces, lower vapor pressure larger molar mass, lower vapor pressure (dispersion forces) higher temp, higher vapor pressure melting point: liquid and solid have identical vapor pressures |
question
| Phase Diagrams |
answer
| solid/liquid line sloped negative: solid less dense than liquid, melting point decreases as pressure increases positive: solid more dense than liquid, melting point increases with pressure |
question
| Henry's Law: gas solubility and pressure |
answer
| C=kP solubility increases when pressure increases C=concentration of dissolved gas P=partial pressure of gas solute above solution k=constant for solution |
question
| Molality |
answer
| moles solute/kg solvent |
question
| Temperature and Gas Solubility |
answer
| gas solubility in liquid typically decreases when temp increases |
question
| Vapor Pressure of Solutions |
answer
| nonvolatile solute lowers vapor pressure of solvent Raoult's Law: Psolution=Xsolvent x Pinitial of solvent (modified when both components are volatile) |
question
| Colligative Properties: depend only on number of solute particles |
answer
| Boiling Point Elevation: ?T=Kb x molality of solute kb=molal boiling-point elevation constat Freezing Point Depression: ?T=Kf x molality of solute Osmotic Pressure: ?=MRT, M=molarity, T=kelvin temp, isotonic=identical, hyper=more concentrated solvent goes out, hypo=less concentrated, solvent comes in |
