CH353
- Physical Chemistry I Spring 2012, Unique 52135 Lecture Summary, 1 February 2012 |

A
Bit More on Paths: The last important pathway we
will talk about is when q = 0. This is called an
adiabatic path. By setting deltaU = w, we
derived the following equation:Cv/nR ln (Tf/Ti) = ln (Vi/Vf)We then manipulated this equation further to put it in a form that is easier to solve plug-and-chug style, but this is the important result. Thermochemistry: We then went on and
discussed the topic of thermochemistry, the science of the flow of
heat due to chemical transformations:Reactant --> Product +/- heat In chemical thermodynamics we almost always are interested in energies at constant pressure, therefore in reaction enthalpies of a system. Because enthalpy is a state function, by defining a standard state of P = 1 bar and T = 298 K, we
can tabulate enthalpies of formation for any substance under that
standard, then use that information to calculate a reaction enthalpy
under any set of circumstances, even those far away from the
standard state. |