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Proof: S (or Entropy) is a Valid State Variable

By Salman Khan - Khan Academy
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Lecture Description

Prroof that S (or entropy) is a valid state variable.

Course Description

Course Index

  1. Introduction to the Atom
  2. Orbitals
  3. More on Orbitals and Electron Configuration
  4. Electron Configuration 1
  5. Electron Configuration 2
  6. Valence Electrons
  7. Groups of the Periodic Table
  8. Periodic Table Trends: Ionization
  9. Other Periodic Table Trends
  10. Ionic, Covalent, and Metallic Bonds
  11. Molecular and Emperical Formulas
  12. The Mole and Avogadro's Number
  13. Formula From Mass Composition
  14. Another Mass Composition Problem
  15. Balancing Chemical Equations
  16. Stoichiometry
  17. Stoichiometry: Limiting Reagent
  18. Ideal Gas Equation: PV=nRT
  19. Ideal Gas Equation Example 1
  20. Ideal Gas Equation Example 2
  21. Ideal Gas Equation Example 3
  22. Ideal Gas Equation Example 4
  23. Partial Pressure
  24. States of Matter
  25. States of Matter Follow-up
  26. Specific Heat, Heat of Fusion and Vaporization
  27. Chilling Water Problem
  28. Van Der Waals Forces
  29. Covalent Networks, Metallic, and Ionic Crystals
  30. Vapor Pressure
  31. Suspensions, Colloids and Solutions
  32. Solubility
  33. Boiling Point Elevation and Freezing Point Supression
  34. Introduction to Kinetics
  35. Reactions in Equilibrium
  36. Mini-video on Ion Size
  37. Keq Intuition
  38. Keq Derivation Intuition
  39. Heterogenous Equilibrium
  40. Le Chatelier's Principle
  41. Introduction to pH, pOH, and pKw
  42. Acid Base Introduction
  43. pH, pOH of Strong Acids and Bases
  44. pH of a Weak Acid
  45. pH of a Weak Base
  46. Conjugate Acids and Bases
  47. pKa and pKb Relationship
  48. Buffers and Hendersen-Hasselbalch
  49. Strong Acid Titration
  50. Weak Acid Titration
  51. Half Equivalence Point
  52. Titration Roundup
  53. Introduction to Oxidation States
  54. More on Oxidation States
  55. Hydrogen Peroxide Correction
  56. Redox Reactions
  57. Galvanic Cells
  58. Types of Decay
  59. Half-Life
  60. Exponential Decay Formula Proof
  61. Introduction to Exponential Decay
  62. More Exponential Decay Examples
  63. Macrostates and Microstates
  64. Quasistatic and Reversible Processes
  65. First Law of Thermodynamics/Internal Energy
  66. More on Internal Energy
  67. Work from Expansion
  68. PV-diagrams and Expansion Work
  69. Proof: U=(3/2)PV or U=(3/2)nRT
  70. Work Done by Isothermic Process
  71. Carnot Cycle and Carnot Engine
  72. Proof: Volume Ratios in a Carnot Cycle
  73. Proof: S (or Entropy) is a Valid State Variable
  74. Thermodynamic Entropy Definition Clarification
  75. Reconciling Thermodynamic and State Definitions of Entropy
  76. Entropy Intuition
  77. Maxwell's Demon
  78. More on Energy
  79. Efficiency of a Carnot Engine
  80. Carnot Efficiency 2: Reversing the Cycle
  81. Carnot Efficiency 3: Proving That it is the Most Efficient
  82. Heat of Formation
  83. Hess's Law and Reaction Enthalpy Change
  84. Gibbs Free Energy and Spontaneity
  85. Gibbs Free Energy Example
  86. Rigorous Gibbs Free Energy/Spontaneity Relationship
  87. A Look at a Seductive But Wrong Gibbs/Spontaneity Proof
  88. Stoichiometry Example Problem 1
  89. Stoichiometry Example Problem 2
  90. Limiting Reactant Example Problem 1
  91. Empirical and Molecular Formulas from Stoichiometry
  92. Example of Finding Reactant Emperical Formula
  93. Stoichiometry of a Reaction in Solution
  94. Another Stoichiometry Example in a Solution
  95. Molecular and Empirical Forumlas from Percent Composition
  96. Acid Base Titration
  97. Spectrophotometry Introduction
  98. Spectrophotometry Example
  99. Hess's Law Example
  100. Vapor Pressure Example
  101. Change of State Example