Chem 152 - midterm 2 - UW Complete Questions And Answers

System - The portion of the universe we have singled out for study surroundings - Everything else in the universe universe - System and surroundings work - the action of a force through a distance heat - Transfer of energy from hotter to colder object heat capacity - The amount of heat needed to raise the temperature by 1 K Heat Tax - Increase in surroundings comes from the heat from the system Kinetic energy - Energy of motion potential energy - Energy of an object by virtue of its position or composition thermal energy - Energy associated with the temperature of an object energy - the capacity to do work or produce heat Enthalpy - The heat content of a system Entropy - A measure of the number of energetically equivalent ways of arranging the components of a systemGibbs free energy - the maximum amount of non-expansion work that can be extracted from a thermodynamically closed system in a reversible process Path function - A property of the system that depends on the route taken from initial to final conditions State function - The property of the system that depends upon only the initial and final conditions not the processes used Standard state - Pure substance in its most stable form at one ATM pressure Exothermic - Produces heat and has negative Q value Endothermic - absorbs heat and has positive Q value Calorimetry - measurement of heat flow Spontaneous - any process that occurs without ongoing outside intervention because it increases the entropy of the universe Reversible - The system and surroundings can be returned exactly to original conditions without increasing the entropy of the universe Irreversible - The system might be returned to its original conditions, but the surroundings are changed in a permanent way isothermal - A process in which the systems temperature does not change (delta U and delta H is 0)Isochoric - A process in which the systems volume does not change Isobaric - A process in which the systems pressure does not change Adiabatic - no heat exchange (delta S of system is 0) Electromagnetic energy - Energy carried through space by electromagnetic waves Thermodynamics - The energy changes that occur in chemistry Law of Conservation of Energy - Energy can be neither created nor destroyed. It is converted from one form to another. Isolated System - A system that exchanges neither matter nor energy with its surroundings. Closed System - a system that exchanges energy but not matter with the surroundings Open System - A system that exchanges both matter and energy with its surroundings First law of Thermodynamics - the total energy of the universe is constant Activation Energy - Energy needed to overcome initial hurdle to initiate a reaction Internal Energy (U) - the total amount of kinetic and potential energy a system possesses Non-Expansion work - work that does not involve a change in volume of the system Expansion work - work needed to change the volume of the systemMolar Heat Capacity - heat capacity per mole Specific Heat Capacity - Heat capacity per gram Hess's law - if a reaction can be expressed as a series of steps, then the delta H for the overall reaction is the sum of the reaction enthalpies of each step Standard Enthalpy change - the enthalpy change when all reactants and products are in their standard states Standard Enthalpy of formation - enthalpy change if 1 mole of compound in standard state were formed directly from its elements Second Law of Thermodynamics - The total entropy change of the universe must be positive for any spontaneous process Third Law of Thermodynamics - For a perfect crystal at absolute zero, the entropy is zero Cycles - the sum of all steps in a cycle is 0 for any state function