Thermodynamics Flashcards
dG formula
dG = dH - T * dS
dG < 0
Spontaneous
dG > 0
non-spontaneus
dH < 0
exothermic [heat release]
dH > 0
endothermic [heat absorb]
dH>0 and dS>0
only spontaneous at high T
dH < 0 and dS > 0
spontaneus at all T
dH > 0 and dS < 0
never spontaneous at any T
Work
w = - Pressure\dVolum
First Law of thermodynimcs
formula
dU = q + w = T*dS - P\dV
u - change in internal energy of system
q - heat T*dS
First Law of thermodynamics
Energy can be converted from one form to another, but the total energy of an isolated system is constant
Second law of thermodynamics
total entropy of an isolated system does not decrease.
Sublimation
solid -> gas [always endothermic]
deposition
gas -> solid [exothermic]
Vaporization
liquid -> gas [endothermic]
condensation
gas -> liquid [exothermic]
Triple point
coexistance of solid, liquid, gas
triple point co2
-56,6 C
triple point water
0.01 C
when liquid boils?
when its vapor pressure equals external pressure
