Chapter 18: Electrochemistry Flashcards
What is electrochemistry?
Transformation between electrical and chemical energy
What are redox reactions and what are the aspects of it?
The sum of two half reactions:
Reduction: reactant gains electrons
Oxidation: reactant loses electrons
*this happens simultaneously
*cross out electrons on opposite sides
Being reduced: oxidizing agent
Being oxidized: reducing agent
What is the oxidation state of an element in its pure form?
zero
What is an electrochemical cell?
Either voltaic or electrolytic cell
V: chemical energy to electrical energy by spontaneous redox reaction
E: electrical energy to chemical energy non-spontaneous
What are the aspects of voltaic cell?
Anode (-): oxidation occurs here
Cathode (+): reduction occurs here
Electrons: from anode to cathode
Chemical reaction used to power something
What is electricity?
It is the migration of electrons
What is the function of a porous salt bridge?
It balances out charges between compartment to prevent the aggregation of charge build ups
What are the aspects of a electrolytic cell?
Cathode (-)-reduction to anode (+)-oxidation,
Electrical energy to chemical energy
What is the standard reduction potential (E*)?
the potential of a half-reaction at standard state (25*C)
What is the standard cell potential (E*cell)?
how forcefully electrochemical cell pumps electricity through circuit
What is the E* cell equation and how is it used?
Ecell = E cathode - E* anode
cathode & anode values are found in the appendix but you must know what is being oxidized and what is being reduced.
