Corrosion Specialist Certification Exam
1.
Corrosion is fundamentally defined as:
A. Surface discoloration only
B. Chemical or electrochemical degradation of a material
C. Change in metal density
D. Hardening of metal in water
✅ Answer: B
Explanation: Corrosion is the deterioration of a material
(commonly metal) due to chemical or electrochemical
reactions with the environment.
2.
In electrochemical corrosion, the anode is the metal area
that:
A. Gains electrons and is protected
B. Loses electrons and corrodes
C. Has no current flow
D. Is always stainless steel
✅ Answer: B
Explanation: At the anode, metal atoms lose electrons
(oxidation) and go into solution—this is where corrosion
occurs.
,3.
The cathode in a corrosion cell is the region where:
A. Metal dissolves
B. Reduction reactions occur
C. Rust forms
D. Electron loss happens
✅ Answer: B
Explanation: Corrosion reactions involve oxidation at anode
and reduction at cathode. Cathodes gain electrons and do not
corrode.
4.
Rust (Fe₂O₃·H₂O) forms in:
A. Dry pure oxygen
B. Presence of oxygen + water
C. Pure nitrogen gas
D. Vacuum
✅ Answer: B
Explanation: Rusting requires both oxygen and moisture to
form hydrated iron oxide.
5.
Which metal acts as sacrificial anode to protect steel?
A. Copper
B. Zinc
C. Gold
,D. Tungsten
✅ Answer: B
Explanation: Zinc is less noble than steel, so it corrodes
(sacrifices) to protect steel.
6.
Galvanic corrosion occurs when:
A. Two dissimilar metals are electrically connected in
electrolyte
B. Metal is stored indoors
C. Stainless steel is polished
D. Surface is painted
✅ Answer: A
Explanation: Dissimilar metals form an electrochemical cell
where the more active metal corrodes.
7.
Which metal is most cathodic (noble)?
A. Aluminum
B. Magnesium
C. Gold
D. Zinc
✅ Answer: C
Explanation: Gold is one of the most noble metals and resists
corrosion.
, 8.
pH strongly affects corrosion because:
A. High acidity accelerates corrosion
B. Lower acidity stops corrosion
C. Acids reduce conductivity
D. Neutral pH destroys metal
✅ Answer: A
Explanation: Acidic environments increase metal dissolution.
9.
Uniform corrosion is:
A. General thinning over entire surface
B. Very localized, needle-like pits
C. Cracking due to stress only
D. Corrosion under paint only
✅ Answer: A
Explanation: Uniform corrosion attacks evenly and is the
simplest to predict.
10.
Pitting corrosion is dangerous because:
A. It is slow and harmless
B. Creates deep localized penetration
C. Only affects aluminum
D. Prevents stress cracking
✅ Answer: B
1.
Corrosion is fundamentally defined as:
A. Surface discoloration only
B. Chemical or electrochemical degradation of a material
C. Change in metal density
D. Hardening of metal in water
✅ Answer: B
Explanation: Corrosion is the deterioration of a material
(commonly metal) due to chemical or electrochemical
reactions with the environment.
2.
In electrochemical corrosion, the anode is the metal area
that:
A. Gains electrons and is protected
B. Loses electrons and corrodes
C. Has no current flow
D. Is always stainless steel
✅ Answer: B
Explanation: At the anode, metal atoms lose electrons
(oxidation) and go into solution—this is where corrosion
occurs.
,3.
The cathode in a corrosion cell is the region where:
A. Metal dissolves
B. Reduction reactions occur
C. Rust forms
D. Electron loss happens
✅ Answer: B
Explanation: Corrosion reactions involve oxidation at anode
and reduction at cathode. Cathodes gain electrons and do not
corrode.
4.
Rust (Fe₂O₃·H₂O) forms in:
A. Dry pure oxygen
B. Presence of oxygen + water
C. Pure nitrogen gas
D. Vacuum
✅ Answer: B
Explanation: Rusting requires both oxygen and moisture to
form hydrated iron oxide.
5.
Which metal acts as sacrificial anode to protect steel?
A. Copper
B. Zinc
C. Gold
,D. Tungsten
✅ Answer: B
Explanation: Zinc is less noble than steel, so it corrodes
(sacrifices) to protect steel.
6.
Galvanic corrosion occurs when:
A. Two dissimilar metals are electrically connected in
electrolyte
B. Metal is stored indoors
C. Stainless steel is polished
D. Surface is painted
✅ Answer: A
Explanation: Dissimilar metals form an electrochemical cell
where the more active metal corrodes.
7.
Which metal is most cathodic (noble)?
A. Aluminum
B. Magnesium
C. Gold
D. Zinc
✅ Answer: C
Explanation: Gold is one of the most noble metals and resists
corrosion.
, 8.
pH strongly affects corrosion because:
A. High acidity accelerates corrosion
B. Lower acidity stops corrosion
C. Acids reduce conductivity
D. Neutral pH destroys metal
✅ Answer: A
Explanation: Acidic environments increase metal dissolution.
9.
Uniform corrosion is:
A. General thinning over entire surface
B. Very localized, needle-like pits
C. Cracking due to stress only
D. Corrosion under paint only
✅ Answer: A
Explanation: Uniform corrosion attacks evenly and is the
simplest to predict.
10.
Pitting corrosion is dangerous because:
A. It is slow and harmless
B. Creates deep localized penetration
C. Only affects aluminum
D. Prevents stress cracking
✅ Answer: B
