Gibbs Free Energy – Notes
Watch Paul Anderson’s YouTube video on the topics of Gibbs Free Energy. As you watch, try to answer
the questions below.
http://www.youtube.com/watch?v=DPjMPeU5OeM&feature=BFa&list=PLFCE4D99C4124A27A
Write the equation for Gibbs Free Energy:___________________________________________________
What does Mr. Anderson prefer to call “free energy.”_________________________________________
What is a spontaneous reaction?__________________________________________________________
Define Enthalpy (H) ____________________________________________________________________
In a spontaneous reaction what happens to enthalpy (H) _______________________________________
Where is potential energy found in biology?_________________________________________________
Define Entropy (S) _____________________________________________________________________
In a spontaneous reaction what happens to entropy (S)________________________________________
In a spontaneous reaction what happens to temperature (T)____________________________________
To summarize spontaneous reactions for each variable:

Enthalpy (H) will ↑
or
↓
resulting in a
↑
or
↓
in free energy (G)

Entropy (S) will
↑
or
↓
resulting in a
↑
or
↓
in free energy (G)

Temp. (T) will
↑
or
↓
resulting in a
↑
or
↓
in free energy (G)
∆G < 0 _____________________________________________________________________________
∆G > 0 ______________________________________________________________________________
∆G = 0 ______________________________________________________________________________
Overview of Cellular respiration:
Glucose → CO2 + H2O

more or less

release or store energy

∆G = __________________kcal/mole

What is needed to get this reaction started:_________________________________
random
↑
↑
or
↓
entropy (S)
or
↓
enthalpy (H)
Overview of Photosynthesis:
CO2 + H2O + Sun + Plant → Glucose

more or less

release or store energy

∆G =_______________________kcal/mole

Where does activation energy come from?__________________________________________
random
↑
↑
or
↓
entropy (S)
or
↓
enthalpy (H)
What is the energy coinage of a cell:______________________________________________________
ATP to ADP:
∆G = __________________kcal/mole
ADP to ATP:
∆G = __________________kcal/mole
Sun to Plant
∆G < 0 or
Photosynthesis
∆G>0
∆G < 0 or
Exergonic
∆G>0
or
Exergonic
∆G>0
Endergonic
or
Exergonic
Endergonic
Cellular Respiration (Glucose to ATP)∆G < 0
or
or
ATP to ADP
∆G < 0 or
∆G>0
Exergonic
or
Endergonic
ADP to ATP
∆G < 0 or
∆G>0
Exergonic
or
Endergonic
Endergonic
Draw a free energy diagram for cellular respiration and a free energy diagram for photosynthesis in the
space below:
Cellular Respiration
Photosynthesis