chapter 2 continued 1 Flashcards
Metals that are ______ negative in the electromotive force series will corrode in comparison to the other metal which is less negative
More
The farther apart the two metals are int eh electromotive force series, the ______ the potential difference between the two, and the greater the ______will take place on the more _______ surface.
greater
corrosion
negative
The rate of galvanic corrosion is not only determined by the _______ position of the metals in the EMF series, but also by the ______ area of the metal.
relative
exposed
_____ the use of combinations of metals that have potentials that are _______ separated in the galvanic series.
avoid
widely
______ joints of _______ metals when possible.
insulate
dissimilar
paint or coat all ______ when possible. Avoid painting the _____ metal only.
surfaces
anodic
Seal _______ (close-fit) surfaces
Faying
Apply _____ coatings to _____ the potential difference between dissimilar metals.
metallic
reduce
_____ threaded connections when dissimilar metals are used.
avoid
An ______ concentration cell commonly develops where two steel plates overlap. The also develop under _____rivets, under loose ____, and under ____paint films
Oxygen
cocked
washers
loose
A pile of sand on a metal surface can also create an ________ concentration cell because the available oxygen in the solution surrounding the pile of sand is _______ than under the sand.
Oxygen
greater
In a metal ion concentration cell, the corrosion reaction is similar to the oxygen concentration cell, the difference being that the concentration of ______ _____ in one place is ______than at another.
metal ions
greater
to prevent crevice corrosion
use _____ joints in preference to _____ or _____ joints
_____ OR ______ unavoidable crevices, using noncorrosive materials
minimize the ____ between metal, and ______ plastic debris
welded bolted or riveted
caulk or seal
contact plastic
to prevent crevice corrosion
avoid contact with materials that are known to contain ________ ______ because they ______ the cell effect.
avoid sharp corners, ______, and ______ where debris can accumulate.
where a crevice is inevitable coat thoroughly both surfaces before the are ________
corrosive elements accelerate
ledges and pockets
joined
pH is the ______ logarithm of the hydrogen ion concentration in a solution .
water is equal pH of _______
acids pH is less than ____
alkalies range from ___ to ____
NEGATIVE
7
7
7 TO 14