CHEM 1B Lecture Notes - Lecture 3: Thermodynamics, Closed System
Document Summary
Audio recording started: 2:02 pm friday, january 13, 2017: state functions have no memory of how the system arrived at its current condition. State of a chemical system is described fully by only a few (dependent) parameters: U = ufinal - uinitial: closed system = constant energy. Usystem = - usurr: system and surroundings exchange energy through work & heat. U = q (heat) + w (work) Work done in the system work done by the system. Energy flows into system energy flows out of the system. A cylinder and piston assembly (the system) is heated by a flame. The contents of the cylinder expland, doing work on the surroundings. = + 593 joules - 289 joules = 303 joules: quantifying heat and work. Heat: transfer of thermal energy because of a temperature difference. Heat flows from hot objects to cold objects. Stops flowing when it reaches the same temperature which is called thermal equilibrium: temperature changes and heat capacity.
