Chemistry 102 Final Exam Flashcards
Define Intermolecular Forces
Forces of ATTRACTION between atoms and substances
Dispersion
Type of attraction seen in EVERY substance
Dipole-Dipole
Type of attraction seen only in POLAR substances
Hydrogen Bonds
Only bond with F.O.N
The strongest intermolecular force is
Dipole - Dipole Bonds
Phase Transitions
Changing from phases to phases
Phase Transitions (Name and Formula) : Liquid to Gas
Vapor to Condensation - ^Hvap
Phase Transitions (Name and Formula) : Solid to Liquid
Melting to Boiling - ^Hfus
Phase Transitions (Name and Formula) : Solid to Gas
Sublimation to Deposition - ^Hfus + ^Hvap
Endothermic or Exothermic
Exo = Vapor to Condensation End = Sublimation to Deposition and Melting to Boiling
Triple Point (1) and Critical Point (2)
(1) Point where all phases are equal
(2) Highest temperature which substance exist in liquid
Heat during a phase transition
- Q1 = ms^t
- (Grams/Molar Mass) * ^Hvap
- Q2 = ms^t
- Combine
Clausius-Clapeyron equation
Heat and Pressure of Vaporization
ln(P2/P1)= ∆Hvap/R * (1/T1 - 1/T2)
Crystalline structure: Simple Cubic
Unit Cell = 8 cn * 1/8 atom = 1 atom
Coordination Number = 6 atoms inside
Crystalline structure: Body-centered Cubic
Unit Cell = 8 cn with 1 * 1/8 atoms = 2 atoms
Coordination Number = 8 atoms inside
Crystalline structure: Face-Centered Cubic
Unit Cell = 8 cn with 1 * 1/18 and 6 cn * 1/2 = 4
Coordination Number = 12 atoms inside
Electrolytes
Substances that dissolves in H20 and goes though a chemical/physical change
IONIC electrolytes
Electrolytes that occur when water and polar molecules combine with IONs and go through dissociation
Henry’s law
Solubility of a gas in a liquid will always be PROPORTIONAL to the pressure of the gas over the solution
Cg = kPg
Formula for Henry’s Law
Cg = Concentration of dissociation
k = Constant
Pg = Pressure of the gas
Molarity
mole of SOLUTE / liter of SOLUTION
Molality
mole of SOLUTE / mass of SOLVENT
Percent by mass
mass of SOLUTE / mass of SOLUTION
solution = solute + solvent
Mole fraction
moles of substance A / moles of all substances
Roult’s law
The PARTIAL pressure exerted by any component of an IDEAL solution is EQUAL to the pressure of the PURE component MUTLIPLIED by MOLE FRACTION
Roult’s Law Formula
Pure(vapor) - Pure(amount) = Mole fraction (solute) * Pure(vapor)
Boiling Point Elevation
a. Have to find Change in Tb = Boiling Point of solution - Boling Point of Pure
b. Change Tb = Molality * Boiling Point constant (K)
Freezing Point Depression
a. Have to find Change in Tf = Freezing Point of solution - Freezing Point of Pure
b. Change Tf = Molality * Freezing Point constant (K)
Osmotic Pressure Definition
The osmotic pressure is the right about pressure enough to preventing osmosis
Osmotic Pressure Formula
Osmotic P = the molarity (mol/l) * 0.0821 L/atm * temperature K
Van’t Hoff factor definition
True number of particles AFTER dissolved / Formula number INITALLY dissolved
Van’t Boiling Point Formula
Tb = iKbm
Van’t Freezing Point Formula
Tf = iKfm
Van’t Osmotic
Osmotic = iMRT
“Reaction Rate” definition
a. Change in the CONCERTATRATION of a reactant/product with time
b. ALWAYS expressed in M/s
Different type of Reaction Rates
Average - Reaction PROCCEEDS over time
Instantaneous - Reaction PROCCEDS at a SPECIEC time
Initial - Occurs at START
“Rate Law” definition
Express the relationship between REACTION RATE to the RATE CONSTANT
Rate Law: Order 0
Standard Formula: -∆A/∆T=K
Formula to find “A”: [A] =Aln -KT
Rate Law: Order 1
Formula to find “K” or the rate constant = ln (A0)/ln(A)*(1/T)
Formula to find “A” or final amount = (A0)*e-KT
Rate Law: Order 2
Standard Formula :
-∆A/∆T=KA2
Activation Energy
The minimum energy necessary to form product during a collision between reactants
Arrhenius Definition
Shows the temperature depending on the rate
Arrhenius Formula
Standard Formula - K= A* e-EA/R(8.314)*T
Formula to find one K - [ln K] = (-EA/R)*(1/T) + ln A
Formula to find two Ks - ln [K2/K1] = (EA/R) * (1/T1 - 1/T2)
In EXO reaction “EA” is
Less than EAR (EAR > EA)
In END reaction “EA” is
More than EAR (EA > EAR)
Equilibrium Constant “K” Definition
The reaction quotient at the equilibrium
Reaction Quotient “Q” Formula
Use same as Reaction Formula
K > 1 (to the right) =Favor products
K< 1 (to the left) = Favor reactants
Reaction Quotient “Q” Definition
The amounts of recants and products present at any point in a reversable reaction
Reaction Quotient “Q” Formula
C(x)D(y) / A(a)B(b) expressed in MOLARITY (Products / Reactants )
Le Chatelier Definition
When a chemical system @ equilibrium is disturbed, returns by countering
Le Chatelier Add/Remove
a. Distributed by ADD = Proceeds to the side that consumes added material
b. Distributed by REMOVE = Proceeds to the side that restores removed material
c. Doesn’t work for pure liquid or solid UNLESS already in the equation
Le Chatelier Rules Concertation
a. Increase Product = Left shift
b. Decrease Product = Right shift
c. Increase Reactants = Right shift
d. Decrease Reactants = Left shift
Le Chatelier Rules Pressure/Volume
a. Increase Pressure = Shift to fewest
b. Increase Volume = Shift to most
c. Decrease Pressure = Shift to most
d. Decrease Volume = Shift to fewest
Calculate pH
-log(OH) or -log(H)
pH + pOH = ?
ALWAYS equal to 14
Kw will always = ?
1.0 * 10 to the -14
Formula for Kw with OH and H
OH + H = Kw (1.0 * 10 to the -14)
To find H = Kw/OH
Ka/Kb Formula
Reactions/ Products
Formula for Kw with Ka and Kb
Kw = Ka* Kb
If given Kw - use “Kw/Kb or Ka”
Henderson-Hasselbalch equation
Used to calculate BUFFER pH
pH = pKa + log (A-/HA)
Titration Steps
a. Before = The O.G substance/chemical will have Higher concertation
b. Equivalent = The O.G and added will have the SAME concertation
c. After = The O.G will have a LOWER concertation
Complex Ion Equilibria
Use the formula - K = Ksp * Kf
Precipitation Predictions
a. Q > K = will precipitate
b. Q < K = unsaturated
c. Q = K = saturated
Solubility (gram/liter)
Number of GRAMS in solute dissolved in 1 LITER of saturated solution
Molar Solubility (mols/liter)
Number of MOLES is solute dissolved in 1 LITER of saturated solution
Product Solubility Constant (Ksp)
The equilibrium between precipitates: A (to power of moles) * B (to power of moles)
Complex Ion Equilibria
Use the formula - K = Ksp * Kf
Entropy
Measure of RANDOMNESS of a system
Formula - Change in S = Sf -SI
Entropy relations to State
Solid < Liquid < Gas
Cause Spontaneous Process
a. H < 0
b. EXO
c. - G
d. S > 0
Formula for Surrounding
Surrounding = -H of system / Temperature
Exo = Surr> 0
End = Surr < 0
Gibbs Free Energy
G = H of system - Tempture * S systems
Gibbs Free Energy @ Equilibrium
G = -RTlnK
R = 8.314
T = always in K
Oxidation verse Reduction
a. Oxidation is the one LOSING an e-
b. Reduction is the one GAINING an e-
Reducing verse Oxidizing Agent
a. Reducing Agent = Oxidation
b. Oxidizing Agent =Reduction
Cathode verse Anode
a. Cathode = Reduction
b. Anode = Oxidation
Cell Notation
a. On the left (the 1st chemical) = the anode
b. On the right = the cathode
Standard Potential
E cell = E cathode - E anode
Always positive in Galvanic cell
Standard Potential and Free Energy Formula 1
G = - mol * F * Ecell
F = 9.648 *10 to 4
Standard Potential and Free Energy Formula 2
E cell = (0.0257/mol )*ln K
