Thermochemistry - Intro to Thermodynamics Flashcards
thermodynamics
the study of the interconversion of heat and kinds of energy; 3 types of system
open system
can exchange mass and energy with the surroundings
closed system
allows the transfer of energy but not mass
isolated system
does not exchange either mass or energy with its surroundings
state functions
properties that are determined by the state of the system, regardless of how that condition was achieved
- magnitude of change depends only on the initial and final states of the system
first law of thermodynamics
energy can be converted from one form to another, but cannot be created or destroyed
- /\U = change in internal energy
- /\U(system) + /\U(surroundings) = 0
equation for the overall change in the systems initial energy
/\U = q + w
what does q stand for
heat
when is q positive
for an endothermic process (heat absorbed by the system)
when is q negative
for an exothermic process (heat released by the system)
what does w stand for
work
when is w positive
work done ON the system
when is w negative
work done BY the system
