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Question 1

resistivity

Answer 1

tendency to migrate or dissociate in soln.

Question 2

degree of ionization

Answer 2

ratio between the number of ionized molecules and the number of molecules dissolved in water

Question 3

Faraday’s 1st law

Answer 3

> amount of material going into or out of system is directly proportional to charge
m ~ Q or m ~ I*t

Question 4

Faraday’s 2nd law

Answer 4

> the weights of material deposited or dissolved by the passage of electricity is proportional to their equivalent weights
m ~ a/Ne
(Ne: valence number of electrons)
(a: molar mass)

Question 5

m =

Answer 5

Ita/Ne*F

Question 6

Q = `

Answer 6

nFni
> ni: moles
> n: charge number or stochiometric coefficient of electrons in the electrode reaction

Question 7

I =

Answer 7

nF (dni/dt) ~ corrosion rate

Question 8

Corrosion rate in mpy (mils/year)

Answer 8

534*W/d*a*t
> W: weight change (mg)
> d: density (gm/cm^3)
> a: area (in^2)
> t: time (hrs)

Question 9

Corrosion rate in mm/yr

Answer 9

87.6*W/d*a*t
> W: weight change (mg)
> d: density (gm/cm^3)
> a: area (in^2)
> t: time (hrs)

Question 10

Solubility of salts: Ksp

Answer 10

= [products]/[reactants]

Question 11

If you exceed Ksp, what happens?

Answer 11

A film forms at the surface of the cathode/anode

Question 12

What happens if Ksp is small?

Answer 12

there is poor solubility, the solid won’t split into ions and it won’t react

Question 13

pH =

Answer 13

-log[H+]

Question 14

Why don’t metals corrode in a reducing environment?

Answer 14

Nothing is there to take electrons

Question 15

ΔG is _____ ______

Answer 15

path independent

Question 16

Grxn =

Answer 16

Gproducts - Greactants

Question 17

_______ says rust is stable, but ______ prevents that from happening

Answer 17

Thermodynamics; kinetics