Gibb’s Energy & Thermodynamics Flashcards
What does entropy describe?
the dispersion of energy
What is a spontaneous process?
occurs without ongoing external intervention
Can spontaneous reactions be slow?
yes
What is entropy? (definition)
a thermodynamic function that increases with the number of equivalent ways to arrange the energy among components of the system to acheive a particular overall state
How is entropy mathematically described? What are the variables?
S=klnW
S is entropy, k is a constant (1.38x10^-23 JK^-1), W is the # of equivalent energy arrangments in the system (microstates)
Explain why water has greater entropy than ice using microstates?
more ways to distribute the energy in water than ice because they can more more, therefore more microstates
What is the second law of thermodynamics?
for any spontaneous process the entropy of the universe increases
How do non-spontaneous reactions effect the entropy of the universe?
do not increase or decrease it
What is the formula for the change in entropy?
deltaS=Sfinal-Sinitial
If entropy increases how does temperature change?
increases
What increases entropy?
adding more particles, melting, sublimation, evaporation
What is the formula for the entropy of the universe?
Suniverse=Ssys + Ssurr
How does the entropy of the surroundings change for exo/endothermic reactions?
exothermic increases the entropy of surroundings
endothermic decreases the entropy of surroundings
At a constant temperature and pressure how can you find the entropy of the surroundings?
deltaSsurr=-deltaHsys/T (kelvin)
How can you find the change in entropy of the universe?
deltaSuni=deltaSsys - deltaH/T