CHEM 122 11th EditionFinal Exam Study Guide Lectures: 31-39Lecture 31 (April 17th)Thermodynamics: energy changes and the flow of energy.- 2factors that act as the driving force for chemical reactions.o Enthalpyo Increase in disorder or randomness of the system.Spontaneity- Spontaneous process: Processes that occur without any outside intervention.- Nonspontaneous Process: Processes that require an outside intervention to occur.Entropy (S): thermodynamic quantity that is measure of the randomness or disorder of a system.- State Functions: depend on the initial and final conditions.- Change in Entropy= Sfinal-Sinital- Solids are highly ordered; liquids have less order; gases have very little ordero Sgas >> Sliquid > SsolidLecture 32 (April 20th)Predicting the Sign Change in Entropy:1. Increase in moles of gases yields an increase in disorder (increase in entropy)2. Increase the number of particles yields an increase in disorder (increase in entropy)- Driving Forces for spontaneous processes:1. Enthalpy: an exothermic change serves as a driving force for the process2. Entropy: an increase in entropy serves as a driving force for a process. - A process that is exothermic and has in increase in entropy is always spontaneous.- A process that is endothermic and has a decrease in entropy is never spontaneous.- A process that exothermic and has a decrease in entropy depends on temperature.- A process that is endothermic and has an increase in entropy depends on temperature.- Reversible: a process that can go back and forth between states along the same path at constant temperature. A process that is at equilibrium will be a reversible process.- Irreversible: a process that goes spontaneously in only one direction. - A spontaneous process is not a reversible processThe Second Law of Thermodynamics: the entropy of the universe increases for a spontaneous process.-∆ Suniv=∆ Ssys+∆ Ssurr o For a reversible process, ∆ Suniv= 0o For an irreversible process ∆ Suniv>0Calculating enthalpy Changes:-nS(products)−¿∑mS(reactants)∆ S=∑¿o n and m are coefficients (moles) in the balanced chemical reactions.Third Law of Thermodynamics: the entropy of a perfect crystalline substance at absolute zero iszero.Lecture 33 (April 22nd)Entropy Change in the Surroundings:-∆ Ssurr=−∆ HsysToT ∆ Suniv=−∆ Hsys+T ∆ SsysGibbs Free Energy: ties these thermodynamic parameters together- G= H-TS- Free Energy: the portion of the energy change that is available to do useful work.- Change in Free Energy: ∆ G=∆ H−T ∆ S∨−T ∆ Sunivo∆ G Is negative then the reaction is spontaneouso : ∆ G is zero then the reaction is at equilibriumo : ∆ G is positive then the reaction is spontaneous in the reverse direction- Standard Free energy change: free energy change for the conversion of reactions in theirstandard states to productso∆ G°=∆ H°−T ∆ S°o Calculate ∆ H°∧∆ S° by using the enthalpy change equationonS(products)−¿∑mS(reactants)∆ S=∑¿ Replace the S’s with H’s and then you have your ∆ H° equation This can also be used to find the values of ∆ G°o Definition of ∆ Gf°: free energy change for formation for one more of a substance from the elements in their standard states.Lecture 34 (April 24th)Standard Gibbs free energy of Formation: free energy change for formation for one mole of a substance from the elements in their standard states.-∆ G°=∑n ∆ Gf°(products)−∑m ∆ Gf°(reactants) o n= moles producto m = moles reactants- the temperature change-over from a spontaneous to a nonspontaneous reaction:o T=∆ H°∆ S°- For any reversible process at constant heat temperature:o∆ S=qrevT- Thermodynamic Equilibrium constant:o∆ G=∆ G°+RTlnQ∆ G°: free energy change under standard conditions∆ G: driving force to reach equilibriumQ: reaction quotientR : ideal gas constant (8.314J/(mol*K)T : Kelvin temperatureo∆ G°=−RTlnKLecture 35 (April 27th)Electrochemistry: deals with the conversion between electrical energy and chemical energy- Volta: invented a crude battery that generated a weak electrical signal- Daniell: constructed the first commercial battery.Oxidation Numbers:- Oxidation-reduction reaction: transfer of electrons from one element to another- Oxidation number rules:1. Oxidation number of any free element is zeroa. Ex.) O2, H2, Cl2 etc.2. The oxidation number of any monatomic ion is equal to its charge. Metals are always positive and in binary compounds, nonmetals have oxidation numbers equal to the charges on their stable monatomic anionsa. Ex) Na+ oxidation number is +13. Sum of all oxidation numbers must equal the charge on the unit.4. Fluorine has an oxidation number of -15. Hydrogen has an oxidation number if +16. Oxygen has an oxidation number of -2- Reduction: gains electrons, the oxidation number reduces, GER- Gain electrons reduction- Oxidation: loss of electrons, oxidation number increases, LEO- Loss electrons oxidation- Requirements for a balanced redox reaction1. Law of conservation mass2. Gains and losses of electrons must be balanced.Lecture 36 (April 29th)Balancing Redox Reactions:1. Divide the reaction into two unbalanced half-reactionsa. Reduction for one equation and the oxidation for the other equation2. Balance atoms other then H and O.3. Balance O by adding H2O4. Balance H by adding H+ a. Make sure now each half reaction obeys the law of conservation of mass.5. Balance the charge of each half reaction by adding electrons to the more positiveside.6. Balance the number of electrons transferred in each half-reaction by multiplying by appropriate coefficients. 7. Add the two half reactions together cancelling out species that appear on apposite sides of the reaction.8. Check to see that the reaction is balanced.a. Atom and charge balanced.Electrochemical cells- Voltaic cells, galvanic cells, and batteries: known as something that uses redox reactions to generate electrical energy.- Salt Bridge: something to neutralize the solutions with a charge to maintain electrical balance.- Electrodes: the site for the oxidation and reduction reactionso Anode: electrodes where oxidation occurso Cathode: the electrode where reduction occurs.- Cell diagram: shorthand representation of the electrochemical cell.- Volt: the potential difference required to impart 1 J of energy to a charge of 1 coulomb (C).o Electron charge= 1.6x10^-19 C- Cell Voltage: potential difference in an electrochemical