PPT-The Third Law, Absolute Entropy and Free Energy

Lecture 4 The Third Law If the entropy of each element in some crystalline state may be taken as zero at the absolute zero of temperature every substance has a finite positive entropy but at absolute zero the entropy may become zero and does so become in the case of perfectly crystalline substances. 6.04. What does ‘Spontaneous’ Mean in Chemistry?. A spontaneous change is a change in a system that proceeds without a net input of energy from an outside source.. Needs some activation energy to get started. Principles of Chemical Reactivity: . Entropy and Free Energy. Chemical Kinetics provides us with information about the rate of reaction and how the reaction proceeds.. Chemical Thermodynamics provides us with information about equilibrium and whether or not a reaction is Spontaneous.. Thermodynamics:. “The laws of thermodynamics describe the essential role of energy and explain and predict the direction of changes in matter. Basic concepts in Big Idea #5. Law of conservation of energy. William A. Goddard III, wag@wag.caltech.edu. Charles and Mary Ferkel Professor of Chemistry, Materials Science, and Applied Physics, . California Institute of Technology. 1. Lecture . 6 and 7, . April . Entropy and Free Energy. Free Energy and Spontaneous Reactions. Many times, the energy (heat) released from a chemical reaction can be used to bring about other changes. This energy is considered to be . Because . entropy is a state function, . the property is what it is regardless of pathway, the . entropy change for a given reaction can be calculated by taking the difference between the . standard entropy. Thermodynamics:. “The laws of thermodynamics describe the essential role of energy and explain and predict the direction of changes in matter. Basic concepts in Big Idea #5. Law of conservation of energy. Chapter 17. Homework. Due with next test. Page 807 . 23-71 . odd. Equations Sheet. Thermodynamics vs. Kinetics. Kinetics deals with . r. ate . of a . reaction, . this depends . on the pathway from reactants to products.. Spontaneous Reaction. A reaction that occurs without outside intervention.. Once it occurs it can be fast or slow.. It can go to completion. (Recall the three products produced :. Precipitate (table F), gas, or water.). Lecture 4 . The Third Law. “. If the entropy of each element in some crystalline state may be taken as zero at the absolute zero of temperature, every substance has a finite positive entropy, but at absolute zero, the entropy may become zero, and does so become in the case of perfectly crystalline substances. See updates on slides . 1, 2, 3, and 8 . Announcements I. Exam 2: Two Weeks from Today (. 10/27. ). Mastering. Some confusion if you pay detailed attention to text (will discuss today. ). Lab: . Quiz 6 – on . Entropy: Criteria for Spontaneity. Second Law of Thermodynamics. Third Law of Thermodynamics. Free Energy . Coupled Reactions. Thermodynamics. The chemistry . that . deals with the flow of energy during a chemical or physical process;. . Metabolism. Metabolism. : the sum total of all the chemical reaction that take place to build up and break down the materials needed in an organism. Catabolism. : the breaking down of complex molecules. 9 weeks. Spontaneity, Entropy and Free Energy. Chapter 17. Equation Sheet. Entropy. Spontaneous or thermodynamically favored (or sometimes just favored) means a reaction happens. The . common . characteristic .