In the past week, we learned about thermodynamics. Thermodynamics is a very important topic in chemistry. Some important ideas about thermodynamics are the first and second law of thermodynamics, standard state conditions, enthalpy, heat of formation, bond energy, hess’s law, heat capacity, specific heat, entropy, and gibbs free energy. The first law of thermodynamics states that energy can only be converted and not destroyed; the energy in the universe is constant. The second law of thermodynamics states that if a process is spontaneous in one direction, it can not be spontaneous in the reverse direction. Standard state conditions are used for state functions: enthalpy change, entropy change, and free energy energy. The conditions are that all gases are at 1 atmosphere pressure, all liquids are pure, all solids are pure, all solutions are at 1 M concentration, and usually the temperature is 25 or 298 kelvin. Enthalpy change is a measure of the energy released or absorbed by the substance; when bonds are formed, energy is released, and when bonds are broken, energy is being absorbed. It is calculated by the formula: Enthalpy change= Enthalpy change in products- Enthalpy of products- Enthalpy of reactants. Heat of formation is the change in energy when one mole of a compound is formed from its component pure elements under standard state conditions(usually at 25C). Bond energy is the energy required to break a bond- it is always an endothermic reaction. Hess’s Law states that if a reaction can be describes as a series of steps, then the enthalpy change for the overall reaction is simply the sum of the enthalpy change for the entire process. Heat capacity is how much the temperature of an object is raised when it absorbs heat. A high heat capacity would mean that by absorbing a large amount of heat would result in a smaller change in temperature. Specific heat is the amount of heat required to raise the temperature of one gram of substance one degree celsius. Entropy is a measure of the “randomness” of a substance. If there are more particles or the particles have more kinetic energy, then it would have more entropy compared to a substance that has less particles and less kinetic energy. Gibbs free energy is a way to measure the spontaneity of a process. This could also be said as measuring how thermodynamically favored a process is. All of these important concepts link together so that reactions can be better understood and so people know how energy behaves.
Many activities allowed me to have a good understanding of thermodynamics. There was a precipitation lab that made students learn about the behaviors of compounds and the characteristics of them. We would test each substance and observe the reaction it had with other substances. Also, whiteboarding helped greatly. I learned a lot from discussing with my table.
I would say my participation was very good. I activity asked questions and I answered some questions from my tablemates. I would rate my participation as a 10/10. My good participation lead me to have a pretty good understanding too. I would rate my understanding as a 9/10. I still am very confused when it comes to things that have to do with equations. I fully understand the other concepts like entropy and or gibbs free energy, but a chemical equation always seems to confuse me. I think I need to rewatch the lectures that have to do with the chemical equations. Then I should do some practice questions that are online or something.
Overall, I have learned a lot from last week. I know a ton about thermodynamics now. I can tell which way energy or heat is going in many everyday processes, like heating a cup of water. It is very cool understanding how basic things in daily works. Now I just want to understand how to use chemical equations to calculate properties from simple reactions. I am still pretty confused on doing that. 
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