Chapter 5 Galvanic cells as a source of energy Flashcards
Accumulator
A secondary, or rechargeable, electrochemical cell
Alkaline Cell
A commercial electrochemical cell with an alkaline electrolyte that is a moist paste rather than a solution
Anode
An electrode at which an oxidation reaction occurs (opposite of RED CAT)
Battery
A combination of cells connected in series
Battery life
A measure of the performance of a battery. It can be the time the battery operates in a device following a full charge or the number of charge-discharge cycles before the battery becomes unusable.
Cathode
An electrode at which a reduction reaction occurs (RED CAT)
Electrochemical cell
A device that converts chemical energy into electrical energy or vice versa
Electrochemical series
A list of half-equations, written as reduction reactions, arranged in order so that the strongest oxidising agents are at the top, left-hand-side of the list.
Electrode
A (usually) solid conductor in a half-cell at which oxidation or reduction reactions occur
Electrolyte
A chemical substance which conducts electric current as a result of dissociation into positively and negatively charged ions, which migrate to the negative and positive terminals of the electric circuit.
Electromotive force
The ‘electrical pressure’ between two points in a circuit, such as the electrodes of an electrochemical cell; a measure of the energy given to electrons in a circuit.
Electronegative
A measure of the ability of an atom of an element to attract electrons.
External circuit
The section of an electrochemical cell in which electrons move. This section of the circuit will include the wires attached to the electrodes.
Galvanic cell/Voltaic cell
A device which converts chemical into electrical energy.
Galvanometer
An instrument for detecting electric current
Half cell
Half an electrochemical cell which contains the oxidant and its conjugate reductant. When two half-cells are combined, a galvanic cell is formed.
Half equation
A balanced chemical equation which shows the loss or gain of electrons by a species during oxidation or reduction.
Inert electrode
An electrode which is not consumed by the reaction occurring at the electrode. The electrode serves only as a conductor of electrons. Precious metals and carbon are typically used as inert electrodes.
Internal circuit
The section of an electrochemical cell in which ions move eg solutions and salt bridge.
Lithium-ion cell
A galvanic cell which generates electricity from the oxidation of lithium embedded in the lattice structure of a graphite rod and the reduction of a metal oxide. The reduction product combines with the lithium ions.
Non-rechargeable cell
A primary galvanic cell
Volt
The unit of potential difference. One volt is defined as one joule per coulomb of charge.
Voltmeter
An instrument for measuring electrical potential difference between two points in an electrical circuit.
