Unit 7
Thermodynamics and Electrochemistry
Thermodynamics and Electrochemistry
19.1 Spontaneous reactions
Describe reactions in terms of spontaneity, reversibility and state functions
Online Problem generator
19.2 Entropy and the 2nd law
Explain what entropy is, its role in reaction spontaneity, and quantify the value of entropy for phase changes (ΔS = qrev/T)
Chemquiz Practice: sc19.2 entropy and 2nd law
19.3 The molecular interpretation of entropy
Explain entropy in terms of molecular motion and explain how it changes with temperature and phase changes.
Quantitatively explain entropy in terms of possible arrangements of atoms/molecules and Boltzmann’s constant (S = klnW)
19.4 Entropy changes in chemical reactions
Qualitatively and quantitatively determine the change in entropy for chemical reactions (ΔS= ∑Sproducts - ∑Sreactants)
19.5 Gibbs Free Energy
Explain the significance of Gibbs free energy and what values are associated with spontaneous reactions, nonspontaneous reactions and reactions at equilibrium. SW calculate the change in Gibbs free energy using known values at standard conditions. ( ΔG= ∑Gproducts - ∑Greactants )
Chemquiz: sc19.5 Gibbs Free Energy
19.6 Free Energy and Temperature
Use both changes in entropy and changes in enthalpy and temperature to determine the spontaneity of a chemical reaction by applying them to the Gibbs Free Energy equation. (ΔG= ΔH – TΔS)
Chemquiz: sc19.6 Free Energy and Temperature
19.7 Free Energy and the equilibrium constant
Calculate the change in free energy at nonstandard conditions as well as relate Keq to standard free energy. (ΔG= ΔGo + RT ln(Q))
Chapter 19 Resources
20.1+2 Redox reactions and balancing them
Determine the oxidation number of various atoms in a compound, identify what has been oxidized/reduced in a chemical reaction, identify oxidizing/reducing agents and balance by using the half reaction method in acidic as well as basic solutions.
Review videos: Determining oxidation states
Chemquiz: Oxidation Numbers
Chemquiz: ID ox/red agents
Chemquiz: Balancing Redox Reactions
20.3 Voltaic Cells
Describe the structure of a voltaic cell and explain what is occurring at an atomic level as well as why it is occurring.
Bonus video: You start at the anode
20.4+5 Cell EMF and Spontaneity of reactions
Objectives: video lesson 20.4 and video lesson 20.5 or text and text
Use standard reduction potentials of each half-cell in a voltaic cell to calculate the electromotive force (EMF, aka. cell potential).
Describe the spontaneity of these cells based upon the EMF and calculate the change in Free Energy (ΔG = -nFE)
20.6 Effect of concentration on cell EMF
Calculate the EMF at nonstandard conditions using the Nernst Equation (E = Eo – RT/nF ln(Q) OR: E = Eo – .0592/n log(Q) ) and relate it to the equilibrium constant.
Electrochemistry Lab
Objectives:
Design and carry out a repeatable lab procedure using the Nernst Equation to determine the concentrations of 2 different solutions (out of 3).
Publish your results for peer review
Activities
20.7 Batteries
Objectives: (text)
Describe the construction of common batteries and explain how they function.
20.8 Corrosion
Explain what corrosion is, its significance in modern society and ways to prevent it.
Cool videos:
20.9 Electrolysis
Describe the process of electrolysis, how it is set up its importance in modern materials and Quantitatively determine the amount of work done during this process.
Chapter 20 Resources