AP Chemistry First Semester
Rules of Octet
1. C, N, O, F always obey Octet; 2. B and Be can disobey Octet with a deficiency; 3. 3rd period elements can disobey Octet with excessive
Rules of Formal Charge
1. F.C.'s should be as close to 0 as possible; 2. Most negative F.C. should be on most electronegative element
Brass
Copper mixed with Zinc
Coulomb's Law
E=(2.31x10-19 Jnm)(q1xq2/r); q1 and q2= charges of ions; r=distance between nuclei
Change in Energy
E=KE+PE=q+w; q=heat; w=work
EPA
Electron Pair Arrangement
Endothermic vs. Exothermic
Endothermic reactions are those that absorb energy; Exothermic reactions release energy
Hess' Law
Energy change is constant in 1 step or many steps
Calorie
Energy to raise 1g of water 1C; 1cal=4.184J
Kinetic Molecular Theory
Gases are dimensionless points with no attraction for each other in constant straight line motion colliding with their container walls with 100% elasticity creating pressure.
Alkanes
General form; *C*n*H*2n+2
Phase Diagram
Graph to summarize conditions where different states of matter are stable
Disproportionation
a substance is reduced and oxidized in the same reaction
ABC...ABC stacking
creates Face Centered Cubic structure, closest packed cubic structure
EPA and Shape of 2 bonds and 2 lone pairs
tetrahedral and bent
EPA and Shape of 4 bonds and 0 lone pairs
tetrahedral and tetrahedral
EPA and Shape of 3 bonds and 1 lone pair
tetrahedral and trig. pyramidal
6 Strong Acids
HCl, HBr, HI, HNO3, H2SO4, HClO4
Heat vs. Temperature
Heat is flow of energy due to temperature differences; Temperature is average KE of a substance
Change in Heat of Salt reactions
Heat of Sublimation+Ionization Energy+Bond Energy+Electron Affinity+Lattice Energy
Homogeneous vs. Heterogeneous
Homo: uniform distribution; Hetero: uneven distribution
Surface Tension
Resistance in liquids to create new surfaces due to an imbalance of forces
Benzene
Ring of carbons with alternating double bonds and hydrogens on the outside
Saturated vs. Unsaturated
Saturated is all carbon atoms bonded to max number of hydrogens; Unsaturated is not
Unit Cell
Simplest repeating pattern in 3-D
Intersticial Space
Space inbetween atoms in a crystal
State of Matter past Critical Point
Supercritical fluid
Formation Reaction
Synthesis reaction with 1mol of product from standard state of elements
EPA and Shape of 3 bonds and 2 lone pairs
trig. bipyramidal and T-shape
EPA and Shape of 2 bonds and 3 lone pairs
trig. bipyramidal and linear
EPA and Shape of 4 bonds and 1 lone pair
trig. bipyramidal and seesaw
EPA and Shape of 5 bonds and 0 lone pairs
trig. bipyramidal and trig. bipyramidal
EPA and Shape of 2 bonds and 1 lone pair
trig. planar and bent
EPA and Shape of 3 bonds and 0 lone pairs
trig. planar and trig. planar
Bond Order
way to tell stability of molecule; should be above 0 is stable; (# of probonding electrons-# of antibonding electrons)/2=Bond Order
Valence Band vs. Conduction Band
Valence Band is probonding, Conduction is antibonding
VSEPR Theory
Valence Shell Electron Pair Repulsion Theory
Bohr's Equation
(-RxZ^2)/n^2; R=Rydberg Constant
Rydberg Constant
-2.178x10^-18 J
Electron Volt
1.6x10^-19 J=1eV
Equivalent amounts of pressure
101.325kPa; 760 torr; 760 mmHg; 1 atm
Orbital Filling Order
1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d 7p
Speed of Light
2.998x10^8 m/s
Planck's Constant
6.626x10^-34 Js
"R" value
8.31 J/molxK; .0821 Lxatm/molxK; 8.31 LxkPa/molxK; 62.4 LxmmHg/molxK
Aliphatic vs. Aromatic
Aliphatic do not contain benzene rings; Aromatic do
Cycloalkanes
Alkanes formed in a ring; *C*n*H*2n
Alkenes
Alkanes with a double bond; *C*n*H*2n
Alkynes
Alkanes with a triple bond; *C*n*H*2n-2
Arrhenius vs. Bronsted-Lowry definition of acids/bases
Arrhenius: Acids give H+, Bases give OH-; Bronsted-Lowry: Acids are proton donors, Bases are proton acceptors
Characteristics of Macromolecular Solids
Atoms held by covalent bonds; High melting point; noncondutive when molten; nonconductive when solid; insoluble; strongest
Octet Rule
Atoms must have 8 valence electrons while bonding
Allotropes
Crystalline Unit Cells with similar empirical formulas and different structures
Molar Mass Equation
DRT/P=M; "Throw dirt on a puddle, you get mud"
Svantis Arrhenius
Discovered Electrolytes
Linus Pauling
Discovered Electronegativity and made the table of Electronegativity values
Ionization Energy Equation
IEmol=1310kJ(Zeff^2/n^2)
General Zeff Periodic Trends
Increasing across row; Decreasing down column
Types of Solids
Ionic, Molecular, Macromolecular, Metallic
Characteristics of Ionic Solids
Ions held by ionic bonds; High melting point; conductive when molten; nonconductive when solid; often soluble; conductive when aqueous
Steel
Iron mixed with Carbon
Einstein's Photoelectric Effect Equation
KE=hv-w; E(photon)=work to eject proton +KE
Intermolecular Forces of Attraction
London Dispersion Forces, Dipole-Dipole Attraction, Hydrogen Bonding; LDF and Dipole-Dipole are Van der Waals forces
Lv=C; E=hv; L=wavelength; v=frequency; C=speed of light; h=Planck's Constant
Lxv=C; H=hv; L=wavelength; v=frequency; C=speed of light; h=Planck's Constant
Reduction vs. Oxidation
Reduction is gaining e-'s; Oxidation is losing e-'s; LEO the lion goes GER; OIL RIG
Characteristics of Metallic Solids
Metallic atoms held by metallic bonds; High melting point; conductive when molten; conductive when solid; insoluble
Organic Compounds Prefixes in Order
Meth, eth, prop, but, pent, hex, hept, oct, non, dec
Characteristics of Molecular Solids
Molecules held by intermolecular forces; Low melting point; nonconductive when molten; nonconductive when solid; solubility depends on solvent "Like dissolves like"; generally nonconductive when aqueous; weakest
Nonpolar covalent vs. Polar covalent vs. Ionic
Nonpolar: 0.0 difference in electronegativity; Polar: 0.1-1.6 difference; Ionic: 1.7 or above difference
Coordination Number
Number of adjacent atoms next to a central atom in crystals
Hydrocarbons
Organic compounds made of only Carbon and Hydrogen
Van der Waal's Law
P(observed)=(nRT/V-nb)-(a(n/V)^2); a=strength of attractive forces; b=L/mol of gas; n=# of particles
Alkyl Radical
Remove one H from an alkane
Can see Waal's Law
P=(nRT)/(V-nb)-a(n/V)^2
Boyle's/Charles'/Gay-Lussac's Laws
PV=K; V/T=K; P/T=K
Ideal Gas Equation
PV=nRT; "Pivnert"
Magnetism
Paramagnetism is unpaired electrons; Diamagnetism is paired electrons; Ferromagnetism is unpaired electrons that line up (Fe, Ni, Co)
Probonding vs. Antibonding
Probonding is lower energy and probability distribution of electrons is inbetween atoms; Antibonding is more energy and probability distribution is either side of atoms
Rate of Diffusion
R1/R2=SQRT(M2/M1)
Aldehydes
Radical attached to a carboxyl (COH)
Phenyl
Radical of benzene
Alcohols
Radical with a hydroxyl (OH) on it
Amines
Radical(s) attached to an ammonia
Ketones
Radicals attached by a C double bonded to an O
Ethers
Radicals attached by an O
Dilution Equation
V1M1=V2M2
Root Mean Square Velocity
U=SQRT(3RT/MM)
Formal Charge
Used for finding most likely non-equivalent resonance structure; FC=# of valence electrons-# of lone pair electrons-.5(# of bonding electrons)
Rigid Structures in Solids
With order (crystalline) and without order (amorphous)
Mole Fractions
X(substance)=n(substance)/n(total)=P(subtance)/P(total)
Zeff vs. Zact
Zeff is how affected an electron is by the nucleus' pull; Zact is the actual pull on an electron by the nucleus
Malleability
ability for metal to be hammered into sheets
Ductility
ability for metal to be wrung into wires
Rectifier
allows current to travel in just one direction
AB...AB stacking
closest packed hexagonal structure
Hybridization
excitation of electrons from s orbitals into p orbitals
Semiconductors
have low conductivity due to gap between valence and conduction bands
Insulators
have too large of a gap between the valence and conduction bands to conduct electricity
EPA and Shape of 2 bonds and 0 lone pairs
linear and linear
Clausius-Clapeyron Equation
ln(vp1/vp2)=(-Hv/R)(1/T2-1/T1); R=8.31J/molxK
DeBroglie Equation
m=h/vL
Volatility
measure of a substance's ability to evaporate
Doped
mixed with
Alloy
mixture of elements with metallic properties
"Sea of Electrons"
molecular orbital in metallic solids, delocalized electrons
Molarity
moles of solute/volume of solution
EPA and Shape of 6 bonds and 0 lone pairs
octahedral and octahedral
EPA and Shape of 4 bonds and 2 lone pairs
octahedral and square planar
EPA and Shape of 5 bonds and 1 lone pair
octahedral and square pyramidal
Vapor Pressure
pressure of liquid vaporated at that temperature
Change in Heat Equation
q=mc(deltaT)
Viscosity
resistance of a liquid to flow
P-Type Semiconductors
semiconductors of a pure substance doped with a substance with fewer valence electrons
N-Type Semiconductors
semiconductors of a pure substance doped with a substance with greater valence electrons
sigma bonds vs. pi bonds
sigma bonds are direct connections between hybridized orbitals; pi bonds are indirect attractions between unhybridized parallel orbitals
Types of Hybridization
sp, sp2, sp3, dsp3, d2sp3