All Flashcards
What is the effect of a negative E°cell?
The reaction is non-spontaneous and requires an external energy source to proceed (electrolytic cell).
What is the effect of a positive E°cell?
The reaction is spontaneous and can be used to generate electricity (galvanic cell).
What is the effect of multiplying a half-reaction by a coefficient when calculating E°cell?
It has no effect on the standard reduction potential (E°).
What happens if the salt bridge is removed from a galvanic cell?
The cell reaction stops because charge neutrality is not maintained, and ion flow is interrupted.
In an electrolytic cell, what happens if the applied voltage is less than the absolute value of E°cell?
The non-spontaneous reaction will not occur.
What are the key differences between galvanic and electrolytic cells?
Galvanic: Spontaneous, E°cell > 0, generates electricity; Electrolytic: Non-spontaneous, E°cell < 0, requires electrical energy.
Compare and contrast oxidation at the anode in galvanic and electrolytic cells.
Both: Oxidation occurs at the anode. Galvanic: Driven by spontaneous redox reaction. Electrolytic: Driven by external power source.
Compare and contrast reduction at the cathode in galvanic and electrolytic cells.
Both: Reduction occurs at the cathode. Galvanic: Driven by spontaneous redox reaction. Electrolytic: Driven by external power source.
Compare electron flow in galvanic and electrolytic cells.
Galvanic: Electrons flow spontaneously from anode to cathode through an external circuit. Electrolytic: Electrons are forced to flow from anode to cathode by an external power source.
Define redox reaction.
A reaction involving the transfer of electrons between chemical species.
Define oxidizing agent.
A substance that gains electrons and is reduced in a redox reaction.
Define reducing agent.
A substance that loses electrons and is oxidized in a redox reaction.
What is electromotive force (EMF)?
The force that pushes electrons in a redox reaction, measured in volts (V).
Define standard reduction potential.
The voltage associated with a reduction half-reaction under standard conditions.
Define galvanic (voltaic) cell.
An electrochemical cell that uses spontaneous redox reactions to generate electricity.
Define electrolytic cell.
An electrochemical cell that uses electrical energy to drive non-spontaneous redox reactions.
Define anode.
The electrode where oxidation occurs.
Define cathode.
The electrode where reduction occurs.