Electrochemistry Flashcards
What does electrochemistry do
Investigates chemucal processes characterized by charges in the oxidation states
How are e- exchanged
Through a circuit
What doesnsalt bridge do
It balances charges in the 2 solutions
How does global reaction of the cell go
Red1+Ox2–>Red2+Ox1
When does current stop going through a circuit
When reaction reaches equilibrium
What does the work the cell depend on
Potential difference E=[V]
What happens with finite flows of circuit
The process is irreversible and potential difference(E) decreases as current increases
When does reverse reaction run in the cell
If potential difference, larger and opposite to that generated spontaneously by the cell, is applied to the system. If the potential applied is equal to the one generated by the cell=>cell is at equilibrium
Formula for work done in reversible reaction in cells
W=ΔrG
What has to happen to the current so the process can be reversible
It must be almost zero. So we apply potential difference between 2 electrodes to stop the current flor and with this happening of spontaneous reaction. That potential difference is called electromotive force(emf) or cell potential E
What is formula for cell potential
ΔrG=-vFE
F=faraday constant
How does nernst equation go
E=-ΔrG/vF=E⊝-RT/vF× ln(Q)
E⊝=-ΔrG⊝/vF
How can equilibrium constant be written through E⊝
E⊝=-RT/vF lnK
K=exp(-vFE⊝/RT)
Formula for electrode reduction potential
E(red/ox)=E(red/ox)⊝-RT/vF×ln a(red)/a(oxL
