Chemistry Chapter 12: Electrochemistry (4 Stars) Flashcards
A __________ cell describes any cell in which oxidation–reduction reactions take place. Certain characteristics are shared between all types of electrochemical cells.
electrochemical
______ are strips of metal or other conductive materials placed in an electrolyte solution.
Electrodes
The _____ is always the site of oxidation. It attracts anions.
anode
The cathode is always the site of ______. It attracts cations.
reduction
Electrons flow from the _____ to the _______
anode to the cathode.
______ flows from the cathode to the anode.
Current
Cell diagrams are shorthand notation that represent the reactions taking place in _______
electrochemical cell.
Cell diagrams are written from _____ to ______with electrolytes (the solution) in between.
anode to cathode
A vertical line represents a _____boundary, and a double vertical line represents a salt bridge or other physical boundary.
phase
Galvanic (voltaic) cells house spontaneous reactions (ΔG < 0) with a _____ electromotive force.
positive
Electrolytic cells houses ______ reactions (ΔG > 0) with a negative electromotive force. These nonspontaneous cells can be used to create useful products through electrolysis.
nonspontaneous
______ cells are a specialized form of a galvanic cell in which both electrodes are made of the same material.
Concentration
Rather than a potential difference causing the movement of charge, it is the concentration gradient between the two solutions.
The charge on an electrode is _____ on the type of electrochemical cell one is studying.
dependent
For galvanic cells, the anode is ______ charged and the cathode is ______ charged.
negatively charged
positively charged.
For electrolytic cells, the ____ is positively charged and the _____ is negatively charged.
anode
cathode
_________ are electrochemical cells that can experience charging (electrolytic) and discharging (galvanic) states.
Rechargeable batteries
Rechargeable batteries are often ranked by energy density—the amount of energy a cell can produce relative to the mass of battery material.
______ is an above-average current transiently released at the beginning of the discharge phase; it wanes rapidly until a stable current is achieved. Cell Potentials
Surge current
A reduction potential quantifies the tendency for a species to gain electrons and be reduced. The higher the reduction potential, the more a given species wants to be ______.
reduced.
Standard reduction potentials (E° red) are calculated by comparison to the standard ______ electrode (SHE) under the standard conditions of 298 K, 1 atm pressure, and 1 M concentrations.
hydrogen
The standard hydrogen electrode has a standard reduction potential of ___ V.
0 V.
Standard electromotive force (E° cell) is the difference in standard reduction potential between the ______
two half-cells.
For galvanic cells, the difference of the reduction potentials of the two half reactions is ______; for electrolytic cells, the difference of the reduction potentials of the two half-reactions is negative.
positive
_______ force and change in free energy always have opposite signs.
Electromotive
When Ecell is positive, ΔG° is _____. This is the case in galvanic cells.
negative
