Correct & Verified
cathode .....ANSWER.....the electrode at which reduction occurs.
electrons flow towards the cathode in the external ciruit
cathodic protection .....ANSWER.....A technique to reduce the
corrosion of a metal surface by making that surface the cathode
of an electrochemical cell.
corrosion .....ANSWER.....the deterioration of a material, usually a
metal, that results from a reaction with its environment.
corrosion inhibitor .....ANSWER.....A chemical substance or
combination of substances that, when present in the environment,
prevents or reduces corrosion.
crevice corrosion .....ANSWER.....localized corrosion of a metal
surface at, or immediately adjacent to, an area that is shielded
,from the environment and full exposure due to the close
proximity of the metal to another surface
electrolyte .....ANSWER.....A chemical substance that promotes
conduction of an electrical current
galvanic series .....ANSWER.....List of metals and alloys arranged
according to their corrosion potentials in a given environment (in
sea water at 25 celcius)
generalized corrosion .....ANSWER.....Corrosion that is distributed
more or less uniformly over the surface of a material
localized corrosion .....ANSWER.....Occurs at discrete sites and
often in areas that are difficult to inspect
mill scale .....ANSWER.....The oxide layer formed during hot
fabrication or heat treatment of metals.
,Passivation .....ANSWER.....a layer of oxides formed on the
surface of a metal that provides corrosion protection (ex stainless
steel)
a reduction of the anodic reaction rate of an electrode involved
in corrosion,
Pitting Corrosion .....ANSWER.....Localized corrosion of a metal
surface that is confined to a small area and takes the form of
cavities called pits.
Return Path (Metallic Pathway) .....ANSWER.....Connects the
anode and cathode, allowing passage of electrons, generated at
the anode, to the cathode
what are the elements of a corrosion cell .....ANSWER.....1. Anode
2. Cathode 3. Metallic pathway 4. Electrolyte
, what happens at anode .....ANSWER.....oxidation. metal dissolves
into electrolyte
what is the function of the electrolyte .....ANSWER.....Allows the
passage of ions to connect the corrosion cell
what is the function of the metallic pathway .....ANSWER.....Allows
the flow of electrons to connect the corrosion cell
The general rules of galvanic corrosion are: .....ANSWER.....The
less noble (or more reactive) metal when connected to a more
noble (or less reactive metal) will corrode preferentially
name at least 5 factors that affect the rate of corrosion
.....ANSWER.....temp, humidity, chemical salts, oxygen, pollutants
General Corrosion .....ANSWER.....Uniform loss of material over
an entire surface and general thinning of affected surface
corrosion that is distributed more or less uniformly