Oana Luca Yale Scientific Fellows Course May 2013 Yale University

1. Equilibrium as a framework for a course in Energy for a synergistic introductory course in Chemistry and Physics Oana Luca Yale Scientific Fellows Course May 2013 Yale University

2. Framework for an Energy Course Intro to Equilibrium Meaning of words [Merriam Webster]: a : a state of intellectual or emotional balance : poise <trying to recover his equilibrium> b : a state of adjustment between opposing or divergent influences or elements c : a state of balance between opposing forces or actions that is either static (as in body acted on by forces whose resultant is zero) or dynamic (as in a reversible chemical reaction when the rates of reaction in both directions are equal)

3. Presenting energy transfer as a consequence of a system trying to reach equilibrium. Structure for each physical and chemical concept • Introductory concepts • Equilibrium condition • Non-equilibrium condition • Energy transfer examples

4. Survey of Types of Energy [from the Internet] • Gravitational - this is the most familiar. A rock poised to roll down a hill has potential energy. A ball thrown into the air gains more and more potential energy as it rises. The higher in the gravity field you go, the more potential energy you gain. Generally speaking, chemistry does not concern itself with the potential energy from gravity, unless you’re dropping your reaction flask- oops! • (b) Electrical - in certain materials, you can move electrons from one area and send them to another. The area losing the electrons becomes more and more positive and the area gaining them becomes negative. The greater and greater the charge difference, the more energy is stored within the system. An example of this is a storm cloud about to impart a lightning strike Earthwards. Fuel cells/Batteries. • (c) Chemical – Thermodynamics. • Certain chemicals have bonds which require little energy to break. This energy must be put into the bond to break it. However, during the course of the chemical reaction, new bonds form which give off MORE energy than that which was put in. Commonly, these reactive compounds are said to "store" energy, but the truth is that the energy released came from a process of first putting in and then getting back more than you put in. • The positional aspect comes from first breaking bonds between atoms (which takes energy) and then rearranging the atoms in new positions to form new bonds (which gives off energy). • If you get back more than you put it, this is called exothermic. The net potential energy converted in the reaction shows up as heat, that is the area around the reaction goes up in temperature. If you get back less than you put in, this is called endothermic. The increase in potential energy of the newly made compounds is reflected in a heat flow from the surroundings into the chemicals, resulting in a temperature drop in the surroundings. • (d) Nuclear - the famous equation E = mc2 governs this source of potential energy. We can consider the mass itself to be potential energy, since it can be converted from a form not being used (while it is the mass), to kinetic energy. This type of potential energy is released (in measurable amounts) during radioactive decay, fission and fusion. wikipedia

5. Two major types of energy • Potential and Kinetic- elaborate on gravitational examples. -mgh+1/2 mv2 constant for a falling block. -pendulum Conservation of energy. Equilibrium and non-equilibrium conditions.

6. Introduction Concepts: -System -States -Reference points -Force

7. Chemical Equilibrium, Redox Equilibrium and Kirchoff’s Laws Intro to Oxidation and Reduction Electrical Intro to circuits Voltage, Currents, Resistance Capacitors Electrolysis and Batteries Prerequisites covered by tidbit- Atomic structure- protons, neutrons, electrons, notion of charge. Tidbit - attached Equilibrium and non-equilibrium conditions.

8. Lecture Layer 1 Lecture Layer 2 Type of energy Mechanical Sonochemistry Intro to acoustics Sound waves “Singing” your reaction into completion Interaction of sound energy with molecules => Chemical reactions. Equilibrium and non-equilibrium conditions. - human inner ear - echolocation ARKIVOC 2002 (iii) 198-218

9. Radiation Lecture Layer 1 Lecture Layer 2 Type of energy Electromagnetic* Intro to wave/particle duality Schrödinger Equation Atomic Orbitals, Quantum numbers, Orbitals/shapes/nodes, Bonding! Low E: Spectroscopic techniques Medium E: Photochemistry High E: Microwave chemistry Energy magnitude => different interactions with matter A poke vs. a push analogy Spectroscopy vs. macroscopic transformations * Schriver and Atkins p3

10. Magnetism Magnetochemistry- Why do we care? Because it’s cool. Sometimes, 4K cool. Molecule + Magnetic Field => Magnetic susceptibility measurements => effective magnetic moment=> Curie Law [or not!] => Single molecule magnet! <= What is that?! Making your processors run faster with SCIENCE! Lecture Layer 1 Lecture Layer 2 Type of energy Magnetochemistry Intro to Magnetism Magnetic Probing equilibrium and non-equilibrium conditions. Other things to teach here: Putting electrons in orbitals. crystal field theory=> # of unpaired electrons! Diamagnetism, Ferromagnetism, Paramagnetism! Intro to Nuclear Magnetic Resonance http://en.wikipedia.org/wiki/Magnetochemistry

11. Lecture Layer 1 Lecture Layer 2 Type of energy Intro to basic thermodynamics Conduction, Convection, Radiation Heat Heats of formation, reactions. Tie in with electrochemistry or vice-versa => Gibbs free energy is the same. Visit him in the Cemetery! Work The usual definition of work is as follows: a force acting over a distance A more wordy definition is: the transfer of energy from one mechanical system to another. It is always completely convertible to the lifting of a weight. [Mechanical-> chemists get no love, until you determine the volume of gas coming out of your reaction with an inverted buret => then your boss loves you] In chemistry, the primary type of work discussed is called "PV work.“ In fact, the concept of work is usually introduced in chemistry in order to discuss PV work's role in the definition of Enthalpy. The result? A good understanding of work tends to "disappear" - especially in introductory classes - since it Enthalpy is however very, very important!! Equilibrium and non-equilibrium conditions. http://www.chemteam.info/Thermochem/Energy-Work-Heat-Temp.html

12. Thermodynamics • heat is not a thing, heat is a process. • heat is the transfer of energy between two objects due to temperature differences. • Notice that the name of the transfer process is heat. What gets transfered is energy. Heat is NOT a substance although it is very convenient to think of it that way. In fact, it used to be thought that heat was a substance. • There is some circularity to the definitions used: • energy does work or produces heat, but(b) heat is a transfer of energy. • “I think this traces back to the fact that energy is something like obscenity: you know it when you see it, but it's very difficult to define. “ • Ultimately, energy is expressed in the motion of substances. If it is moving, it has energy. If it has the capacity to move, there is some potential energy stored away. http://www.chemteam.info/Thermochem/Energy-Work-Heat-Temp.html

13. Temperature – the observable • Generally speaking, the temperature discussed is absolute temperature, measured in Kelvins. Here's the definition: temperature is a property which is directly proportional to the kinetic energy of the substance under examination. • By the way, it's OK to use temperature differences measured in degrees Celsius. That's because the "size" of one degree Celsius equals one Kelvin. Also, the term "degrees Kelvin" is NOT used. Here's another definition I found: temperature is the property which determines the direction heat will flow when two objects are brought into contact. • It turns out that temperature is a rather sophisticated concept Two last points, just by the by: • When two bodies are in thermal equilibrium with a third body, then they must be in thermal equilibrium with each other. This is called the Zeroth Law of Thermodynamics and is the basis for temperature measurements, since the thermometer must come to thermal equilibrium with the object being measured. • An important issue in temperature measurement is the ability to accurately and reroducibly measure temperature. To that end, there are on-going efforts at the international level to set temperature standards and ensure that the scientific world gets good data. A recent issue of discussion concerns how to accurately measure temperatures below 0.1 Kelvin. After all, your ordinary laboratory thermometer just will not do at those very low temperatures. pcmac.org/SiSFiles/Schools/AL/MobileCounty/LeFloreHigh/Uploads/Forms/Thermochemistry Notes.doc

14. The story of the Proton and the Neutron? Type of energy Nuclear E = mc2 Structure of an atom. Protons, neutrons, introduction to the periodic table. Fusion vs. Fission Conservation of mass – not so much Mass defects <= can of worms.

15. Law of Conservation of Mass- Energy There is a scientific law called the Law of Conservation of Mass, discovered by Antoine Lavoisier in 1785. In its most compact form, it states: matter is neither created nor destroyed. In 1842, Julius Robert Mayer discovered the Law of Conservation of Energy. In its most compact form, it it now called the First Law of Thermodynamics: energy is neither created nor destroyed. In 1907 (I think), Albert Einstein announced his discovery of the equation E = mc2 and, as a consequence, the two laws above were merged into the Law of Conservation of Mass-Energy: the total amount of mass and energy in the universe is constant. Generally, textbooks would add, as I am doing, that mass and energy can interconvert[for real!] An interesting historical footnote: during the radioactive decay called beta decay, tremendous amounts of energy were being produced. This was expected, but what was not was that the energy amounts released varied widely for the exact same decay process. The amounts should always have been the same. This was very puzzling to the early researchers and I believe it was Niels Bohr who proposed that the Law of Conservation of Energy was being violated. Of course, this turned out to not be the case. The correct answer was a new particle called the "neutrino," proposed about 1930 by Wolfgang Pauli. The neutrino was finally detected in 1952 (I think) and the discoverers were able to inform Pauli, then near death due to cancer. By the way, the neutrino is a very, very important particle in modern science. You may wish to research how neutrinos were useful in learning about Supernova 1987A. The Law of Conservation of Mass is still a useful idea in chemistry. This is because the energy changes in a chemical reaction are so tiny that they did not affect any measurements. 100 kJ is a typical value for the energy involved in a chemical reaction and it is only about 10¯9 gram. Only recently has such a small amount been able to be accurately measured. The mass loss or gain due to energy loss or gain in a chemical reaction may someday be something that is routinely measured. http://www.chemteam.info/Thermochem/Law-Cons-Mass-Energy.html