02 Electrochemistry and Corrosion Flashcards
electrochemical cell
An _____________ is a device that can generate electrical energy from the chemical reactions occurring in it, or use the electrical energy supplied to it to facilitate chemical reactions in it. These devices are capable of converting chemical energy into electrical energy, or vice versa.
galvanic cell; electrolytic cell
A ____________ converts chemical energy into electrical energy; while ____________ electrical energy into chemical energy
loss
gain
Oxidation is ______ of e-
Reduction is ______ of e-
galvanic cell; electrolytic cell
Spontaneous redox reaction: _______________
Nonspontaneous redox reaction: _______________
water
The presence of ______________ is necessary in order to transport ions to and from the metal, but a thin film of adsorbed moisture can be sufficient.
Galvanic Corrosion
Also called “dissimilar metal corrosion” or wrongly “electrolysis”) refers to corrosion damage induced when two dissimilar materials are coupled in a corrosive electrolyte.
less; more
In a bimetallic couple, the __________ noble material becomes the anode and tends to corrode at an accelerated rate, compared with the uncoupled condition and the __________ noble material will act as the cathode in the corrosion cell
Luigi Galvani
Late 18th century- The bimetallic driving force was discovered through as series of experiments with the exposed muscles and nerves of a frog that contracted when connected to a bimetallic conductor.
Alessandro Volta
1800- the principle was later put into a practical application by first electrical cell, or battery: a series of metal disks of two kinds, separated by cardboard disks soaked with acid or salt solutions.
Sir Humphry Davy
Early 19th century- The principle was also engineered into the useful protection of metallic structures.
Electrolyte
A conductive solution, like saltwater or even tap water, that allows the flow of ions between the anode and cathode.
Electrical connection
A metallic pathway connecting the anode and cathode, allowing the flow of electrons to complete the circuit.
anode; cathode
Less noble: _____________; more noble: _____________.
sacrificial anode
Introducing a more active metal, called a ________________, can be strategically placed to corrode preferentially and protect the desired metal. This principle is used in cathodic protection systems for pipelines and other structures.
coatings
Applying protective _____________ to the anode can create a barrier and impede its interaction with the electrolyte.
Electrode Potential
It is the tendency for an electrode to lose or gain electrons when dipped in the solution of its ions.
1 atm; 298 K; 1 M
Standard Electrode Potential is measured at _____ atm, _____ K, and _____ M.
two
Zinc atoms in the rod undergo oxidation by losing _____ electrons to form zinc ions which go into the solution
-0.76
The reduction potential of zinc electrode is ____________, which implies that ZINC is more electropositive than hydrogen
0.34
The reduction potential of zinc electrode is ____________, which implies that COPPER is more electropositive than hydrogen
anode to cathode
Electrons always flow from __________ to __________.
Current
_____________ is produced in an electrochemical cell while corrosion is occurring.
Electrochemical corrosion
_______________ involves the transfer of electrons from the anode to the cathode.
Corrosion rate
This is the speed at which any given metal deteriorates in a specific environment.
instantaneous
Electrochemical corrosion rate is “________________.”
number of coulombs
Faraday developed the ________________ known as “FARADAY”
Faraday’s First Law of Electrolysis
This law states that: Amount of substance produced at each electrode is directly proportional to the charge flowing through the cell.
electro-chemical equivalent
In Faraday’s First Law of Electrolysis, z is a constant, and known as ______________, and is characteristic of the substance deposited.
Mass of Oxidized Metal
This is the formula for _________________ under Faraday’s First Law of Electrolysis.
Corrosion Rate
This is the formula for _________________ under Faraday’s First Law of Electrolysis.
Electrochemical Process
It is defined as a chemical reaction involving the transfer of electrons between two electrodes in an electrochemical cell.
Luigi Galvani
The galvanic cell is named after _____________, a physician in Bologna, Italy, who published his studies of electrochemical action in 1791.
electrochemical cells
It is a device that converts chemical energy produced in a redox reaction into electrical energy