Chapter 2 Notes (unfinished)

Chapter 2-Thermodynamics

thermodynamics- the study of the transformation of energy, particularly the relationship b/w heat and work
chemistry-revolves around the study of energy
-energy- the capacity to do work
-work- done to achieve motion against an opposing force
system-the part of the universe in which we are interested
surroundings-the region outside the system , from where we observe the system
   3 types open-exchange matter/energy w/surroundings

    closed-exchange energy w/surroundings

         isolated-no exchange of energy or matter
1.) Energy can be exchanged b/w closed system and surroundings
-doing work (PV); expansion work; adiabatic (Q=0, no heat change);
-heating (energy is transferred because of temp differences); diathermic
2.) Both are modes of energy transfer, not forms of energy
-heat vs temp: T is an intensive property, and it determines the direction of energy flow
-heat, “q”, is energy in transit
diathermic-walls that permit heating (or cooling) as a transfer of energy, ex. a metal container
adiabatic-walls that do not permit energy transfer
-expansion means system does work, pushes against an external force

Measure work
-when a system does work, W is negative
-when work is done on the system, W is positive (unit of measure is Joules)
Expansion Work-for reactions that produce gas
W=-Pexternal*deltaV
=measure of work done by the system
-if no Pexternal, no work is done
exothermic-releases energy as heat (feels warm)
endothermic-absorbs energy (feels cool)
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