Impressed current systems are commonly used where large currents are required. Direct current is discharged through one or more anodes into the:

A - Thermoelectric generators B - Electrolyte C - Low resistance backfill D - Structure requiring protection Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 7:

Sacrificial anodes are made of materials like:

A - Graphite or titanium B - Zinc or magnesium C - Copper or aluminum D - Nickel or chromium Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 8:

Passivating inhibitors function by:

A - Being electrodeposited onto mechanical parts B - Forming precipitates on cathodic areas, which slow down the corrosion reactions C - Being added to a system to neutralize acids D - Causing the metal to corrode, creating a protective oxide film Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 9:

Caustic corrosion (caustic gouging) takes place where corrosion products are deposited and is usually found in ______________ areas of the boiler.

A - Low fluid level B - Low heat C - High heat D - High fluid level Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 10:

Cooling water systems are excellent areas for corrosion to take place. All of the following are factors that contribute to corrosion in cooling water systems except:

A - A drop in pH to low levels B - An oxygen-saturated system C - The absence of dissolved solids in the raw water makeup D - High and low temperatures Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct

Question 1:

Passivating inhibitors function by:

A - Being electrodeposited onto mechanical parts B - Causing the metal to corrode, creating a protective oxide film C - Forming precipitates on cathodic areas, which slow down the corrosion reactions D - Being added to a system to neutralize acids Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 2:

Impressed current systems are commonly used where large currents are required. Direct current is discharged through one or more anodes into the:

A - Electrolyte B - Thermoelectric generators C - Structure requiring protection D - Low resistance backfill Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 3:

Caustic corrosion (caustic gouging) takes place where corrosion products are deposited and is usually found in ______________ areas of the boiler.

A - High fluid level B - Low heat C - Low fluid level D - High heat Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 4:

Cathodic protection is the use of indirect current from an external source to oppose the discharge of corrosion current from cathodic areas of a metal structure immersed in a conducting medium or electrolyte such as soil and water.

A - True B - False Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 5:

Ammonia has been used for corrosion control in inert gas systems and is an example of:

A - A passivating inhibitor B - A volatile neutralizer C - An anodic inhibitor D - A cathodic inhibitor Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 6:

Of the following, which is NOT a typical application of galvanic anodes?

A - Internal protection of vessels that are partly filled with water B - Hot spot (small areas of high corrosion) protection on bare buried pipelines. C - Protection of short, well-coated buried pipelines D - External protection of vessels that are partly filled with water Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 7:

Sacrificial anodes are made of materials like:

A - Zinc or magnesium B - Nickel or chromium C - Copper or aluminum D - Graphite or titanium Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 8:

Pitting in boiler metal is caused by:

A - Chlorides B - Oxygen C - Ammonia D - Carbon dioxide Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 9:

Based on the chart shown here, which of the combinations of metals listed would have the greatest tendency for galvanic corrosion when joined?

A - Titanium and copper B - Nickel and monel C - Aluminum bronze and tin D - Nickel and zinc Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 10:

There is one type of corrosion that is most responsible for destructive explosions involving boilers. What is it?

A - Pitting B - Caustic embrittlement C - Caustic corrosion D - Hydrogen damage Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct

PTPR 6006_Corrosion Mechanisms

Question 1:

A cathode:

A - Is the terminal of an electrolytic cell at which oxidation occurs B - Is where electrons flow away from in the external circuit C - Is where cations accept electrons thus being reduced D - Is usually where corrosion occurs as the metal ions enter the electrolyte Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 2:

Galvanic corrosion can occur in a pipe system where all the pipes are made of the same material because:

A - Pairs of cathodes and anodes cannot exist along the surface of a single piece of metal B - Rough surfaces and microscopic imperfections will produce differences in electrical potential C - Small pockets of carbon from the steel making process cause parts of the steel to become more noble D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 3:

Although the mechanism for sulphide cracking is not completely understood, it is agreed that one of the following conditions must be present before the problem can occur:

A - Hydrogen sulphide must be present B - The steel must be completely stress-free C - Low strength steel must be involved D - There must be a total absence of water Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 4:

A reaction in which there is an increase in valence of an atom resulting from a loss of electrons is defined as:

A - Polarization B - Oxidation C - Potential D - Reduction Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 5:

The type of corrosion where an increase in the concentration of hydrogen at the surface of steel causing the hydrogen atoms to diffuse into the steel resulting in a severe loss of ductility is called:

A - Hydrogen embrittlement B - Hydrogen blistering C - Sulphide stress cracking D - Caustic embrittlement Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 6:

Galvanic corrosion occurs when a metal is electrically connected to another metal in the same electrolyte. The rate of galvanic corrosion depends upon the nature of the environment in which the metals exist as well as the:

A - Potential difference between the metals B - Polarization behaviour of the metals C - Distance between the dissimilar metals D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 7:

All of the following are important types of corrosion failure mechanisms associated with waterside boiler corrosion except:

A - Caustic corrosion B - Hydrogen damage C - Pitting D - Sulphate reducing bacteria Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 8:

The type of bacteria that require oxygen to live and grow are referred to as:

A - Aerobic bacteria B - Anaerobic bacteria C - Facultative bacteria D - None of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 9:

When biological corrosion occurs in an environment that is totally lacking in oxygen and high in sulphates, the most likely type of bacterial source of the corrosion is:

A - Salmonella bacteria B - Anaerobic bacteria C - Facultative bacteria D - Aerobic bacteria Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 10:

Dry atmospheric corrosion occurs when metals have the ability to form a stable film in the presence of:

A - Carbon dioxide B - Oxygen C - Hydrogen D - Nitrogen Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct

Question 1:

For sulphide stress cracking to occur, hydrogen sulphide must be present, high-strength steel that is under tensile stress must be involved, and:

A - Sulphide reducing bacteria must be present B - Water must be present C - The process must involve chlorine D - Water must be absent Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 2:

Sulphate reducing bacteria (SRB) are very corrosive in an:

A - Oxygenated environment B - Anaerobic environment C - Aqueous environment D - Aerobic environment Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 3:

Although the mechanism for sulphide cracking is not completely understood, it is agreed that one of the following conditions must be present before the problem can occur:

A - There must be a total absence of water B - Hydrogen sulphide must be present C - The steel must be completely stress-free D - Low strength steel must be involved Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 4:

When biological corrosion occurs in an environment that is totally lacking in oxygen and high in sulphates, the most likely type of bacterial source of the corrosion is:

A - Anaerobic bacteria B - Salmonella bacteria C - Facultative bacteria D - Aerobic bacteria Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 5:

Stray current corrosion differs from galvanic corrosion because stray current corrosion is caused by:

A - An internal source of current B - An external source of current C - An impressed-current cathodic protection system D - The voltage produced in the corrosion cell itself Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 6:

A cathode:

A - Is where cations accept electrons thus being reduced B - Is where electrons flow away from in the external circuit C - Is the terminal of an electrolytic cell at which oxidation occurs D - Is usually where corrosion occurs as the metal ions enter the electrolyte Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 7:

The type of bacteria that require oxygen to live and grow are referred to as:

A - Aerobic bacteria B - Anaerobic bacteria C - Facultative bacteria D - None of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 8:

Although there are a number of environmental conditions that contribute to stress corrosion cracking, what must first exist for this condition to begin?

A - A high copper-sulphate concentration must exist in the process fluid B - There must be a flaw or discontinuity in the metal C - Boiler water must be raised to a pH of between 9 and 11.5 D - There must be multiple layers of moisture Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 9:

A reaction in which there is a decrease in valence of an atom resulting from the gain of electrons is defined as:

A - Potential B - Polarization C - Reduction D - Oxidation Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 10:

The type of corrosion where an increase in the concentration of hydrogen at the surface of steel causing the hydrogen atoms to diffuse into the steel resulting in a severe loss of ductility is called:

A - Hydrogen blistering B - Hydrogen embrittlement C - Caustic embrittlement D - Sulphide stress cracking Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct

Question 1:

Stray current corrosion differs from galvanic corrosion because stray current corrosion is caused by:

A - An internal source of current B - An impressed-current cathodic protection system C - An external source of current D - The voltage produced in the corrosion cell itself Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 2:

Waterside corrosion in boilers can be a serious problem that can cause unscheduled shut downs of steam generators. In order to prevent this a boiler must be carefully monitored so that it maintains a magnetite coating that will help to prevent corrosions. What is the most important requirement to maintaining that coating?

A - Keeping the pH of the boiler water at 7 B - Keeping the pH of the boiler water at 11 C - Keeping the boiler water temperature above 90 degrees C D - Replacing the boiler water every 30 days Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 3:

When biological corrosion occurs in an environment that is totally lacking in oxygen and high in sulphates, the most likely type of bacterial source of the corrosion is:

A - Facultative bacteria B - Anaerobic bacteria C - Aerobic bacteria D - Salmonella bacteria Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 4:

In hydrogen stress cracking, the atoms of hydrogen interact with the metal to induce crack growth, which may lead to fracture. This cracking is in the absence of active corrosion. If there were active corrosion, the cracking would more correctly be termed:

A - Hydrogen blistering B - Galvanic corrosion C - Stress corrosion cracking D - Hydrogen embrittlement Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 5:

Galvanic corrosion occurs when a metal is electrically connected to another metal in the same electrolyte. The rate of galvanic corrosion depends upon the nature of the environment in which the metals exist as well as the:

A - Potential difference between the metals B - Polarization behaviour of the metals C - Distance between the dissimilar metals D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 6:

Galvanic corrosion can occur in a pipe system where all the pipes are made of the same material because:

A - Pairs of cathodes and anodes cannot exist along the surface of a single piece of metal B - Rough surfaces and microscopic imperfections will produce differences in electrical potential C - Small pockets of carbon from the steel making process cause parts of the steel to become more noble D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 7:

An anode:

A - Is where electrons flow toward in the external circuit B - Is the terminal of an electrolytic cell at which reduction occurs C - Is where cations accept electrons thus being reduced D - Is usually where corrosion occurs, as the metal ions enter the electrolyte Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 8:

Sulphate reducing bacteria (SRB) are very corrosive in an:

A - Aqueous environment B - Anaerobic environment C - Aerobic environment D - Oxygenated environment Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 9:

The most destructive source of stray current corrosion is:

A - Direct current B - 110 volt current C - 220 volt current D - Alternating current Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 10:

A reaction in which there is an increase in valence of an atom resulting from a loss of electrons is defined as:

A - Polarization B - Potential C - Oxidation D - Reduction Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct

Question 1:

Waterside corrosion in boilers can be a serious problem that can cause unscheduled shut downs of steam generators. In order to prevent this a boiler must be carefully monitored so that it maintains a magnetite coating that will help to prevent corrosions. What is the most important requirement to maintaining that coating?

A - Keeping the boiler water temperature above 90 degrees C B - Keeping the pH of the boiler water at 7 C - Replacing the boiler water every 30 days D - Keeping the pH of the boiler water at 11 Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 2:

In hydrogen stress cracking, the atoms of hydrogen interact with the metal to induce crack growth, which may lead to fracture. This cracking is in the absence of active corrosion. If there were active corrosion, the cracking would more correctly be termed:

A - Hydrogen embrittlement B - Hydrogen blistering C - Galvanic corrosion D - Stress corrosion cracking Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 3:

The type of bacteria that require oxygen to live and grow are referred to as:

A - Aerobic bacteria B - Anaerobic bacteria C - Facultative bacteria D - None of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 4:

An anode:

A - Is usually where corrosion occurs, as the metal ions enter the electrolyte B - Is where electrons flow toward in the external circuit C - Is where cations accept electrons thus being reduced D - Is the terminal of an electrolytic cell at which reduction occurs Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 5:

Stray current corrosion differs from galvanic corrosion because stray current corrosion is caused by:

A - An impressed-current cathodic protection system B - An external source of current C - The voltage produced in the corrosion cell itself D - An internal source of current Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 6:

For sulphide stress cracking to occur, hydrogen sulphide must be present, high-strength steel that is under tensile stress must be involved, and:

A - Sulphide reducing bacteria must be present B - Water must be present C - Water must be absent D - The process must involve chlorine Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 7:

A cathode:

A - Is usually where corrosion occurs as the metal ions enter the electrolyte B - Is the terminal of an electrolytic cell at which oxidation occurs C - Is where electrons flow away from in the external circuit D - Is where cations accept electrons thus being reduced Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 8:

All of the following are important types of corrosion failure mechanisms associated with waterside boiler corrosion except:

A - Caustic corrosion B - Sulphate reducing bacteria C - Hydrogen damage D - Pitting Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 9:

Dry atmospheric corrosion occurs when metals have the ability to form a stable film in the presence of:

A - Oxygen B - Hydrogen C - Nitrogen D - Carbon dioxide Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 10:

Galvanic corrosion can occur in a pipe system where all the pipes are made of the same material because:

A - Pairs of cathodes and anodes cannot exist along the surface of a single piece of metal B - Rough surfaces and microscopic imperfections will produce differences in electrical potential C - Small pockets of carbon from the steel making process cause parts of the steel to become more noble D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct

Question 1:

In hydrogen stress cracking, the atoms of hydrogen interact with the metal to induce crack growth, which may lead to fracture. This cracking is in the absence of active corrosion. If there were active corrosion, the cracking would more correctly be termed:

A - Stress corrosion cracking B - Hydrogen blistering C - Hydrogen embrittlement D - Galvanic corrosion Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 2:

Galvanic corrosion can occur in a pipe system where all the pipes are made of the same material because:

A - Pairs of cathodes and anodes cannot exist along the surface of a single piece of metal B - Rough surfaces and microscopic imperfections will produce differences in electrical potential C - Small pockets of carbon from the steel making process cause parts of the steel to become more noble D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 3:

An anode:

A - Is where electrons flow toward in the external circuit B - Is where cations accept electrons thus being reduced C - Is the terminal of an electrolytic cell at which reduction occurs D - Is usually where corrosion occurs, as the metal ions enter the electrolyte Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 4:

Sulphate reducing bacteria (SRB) are very corrosive in an:

A - Oxygenated environment B - Aqueous environment C - Aerobic environment D - Anaerobic environment Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 5:

All of the following are important types of corrosion failure mechanisms associated with waterside boiler corrosion except:

A - Sulphate reducing bacteria B - Hydrogen damage C - Caustic corrosion D - Pitting Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 6:

A cathode:

A - Is where electrons flow away from in the external circuit B - Is usually where corrosion occurs as the metal ions enter the electrolyte C - Is where cations accept electrons thus being reduced D - Is the terminal of an electrolytic cell at which oxidation occurs Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): C Marked as: Incorrect _______________________________________________

Question 7:

Although the mechanism for sulphide cracking is not completely understood, it is agreed that one of the following conditions must be present before the problem can occur:

A - There must be a total absence of water B - Low strength steel must be involved C - Hydrogen sulphide must be present D - The steel must be completely stress-free Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 8:

For sulphide stress cracking to occur, hydrogen sulphide must be present, high-strength steel that is under tensile stress must be involved, and:

A - Water must be present B - The process must involve chlorine C - Water must be absent D - Sulphide reducing bacteria must be present Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 9:

When biological corrosion occurs in an environment that is totally lacking in oxygen and high in sulphates, the most likely type of bacterial source of the corrosion is:

A - Facultative bacteria B - Salmonella bacteria C - Anaerobic bacteria D - Aerobic bacteria Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 10:

The type of corrosion where an increase in the concentration of hydrogen at the surface of steel causing the hydrogen atoms to diffuse into the steel resulting in a severe loss of ductility is called:

A - Caustic embrittlement B - Hydrogen embrittlement C - Hydrogen blistering D - Sulphide stress cracking Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct Question 1:

Although there are a number of environmental conditions that contribute to stress corrosion cracking, what must first exist for this condition to begin?

A - There must be multiple layers of moisture B - There must be a flaw or discontinuity in the metal C - Boiler water must be raised to a pH of between 9 and 11.5 D - A high copper-sulphate concentration must exist in the process fluid Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 2:

Sulphate reducing bacteria (SRB) are very corrosive in an:

A - Aerobic environment B - Oxygenated environment C - Aqueous environment D - Anaerobic environment Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 3:

A reaction in which there is an increase in valence of an atom resulting from a loss of electrons is defined as:

A - Oxidation B - Potential C - Polarization D - Reduction Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 4:

For sulphide stress cracking to occur, hydrogen sulphide must be present, high-strength steel that is under tensile stress must be involved, and:

A - The process must involve chlorine B - Water must be absent C - Sulphide reducing bacteria must be present D - Water must be present Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 5:

The type of corrosion where an increase in the concentration of hydrogen at the surface of steel causing the hydrogen atoms to diffuse into the steel resulting in a severe loss of ductility is called:

A - Hydrogen embrittlement B - Sulphide stress cracking C - Caustic embrittlement D - Hydrogen blistering Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 6:

The most destructive source of stray current corrosion is:

A - Direct current B - 110 volt current C - Alternating current D - 220 volt current Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 7:

In hydrogen stress cracking, the atoms of hydrogen interact with the metal to induce crack growth, which may lead to fracture. This cracking is in the absence of active corrosion. If there were active corrosion, the cracking would more correctly be termed:

A - Hydrogen blistering B - Galvanic corrosion C - Stress corrosion cracking D - Hydrogen embrittlement Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 8:

Galvanic corrosion occurs when a metal is electrically connected to another metal in the same electrolyte. The rate of galvanic corrosion depends upon the nature of the environment in which the metals exist as well as the:

A - Potential difference between the metals B - Polarization behaviour of the metals C - Distance between the dissimilar metals D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 9:

All of the following are important types of corrosion failure mechanisms associated with waterside boiler corrosion except:

A - Hydrogen damage B - Sulphate reducing bacteria C - Caustic corrosion D - Pitting Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 10:

A reaction in which there is a decrease in valence of an atom resulting from the gain of electrons is defined as:

A - Polarization B - Reduction C - Oxidation D - Potential Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct

Question 1:

The type of corrosion where an increase in the concentration of hydrogen at the surface of steel causing the hydrogen atoms to diffuse into the steel resulting in a severe loss of ductility is called:

A - Sulphide stress cracking B - Hydrogen blistering C - Caustic embrittlement D - Hydrogen embrittlement Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 2:

Stress corrosion cracking is the cracking of a metal that requires the simultaneous action of:

A - A corroding substance and an applied or residual tensile stress B - A non-corrosive substance and an applied or residual tensile stress C - A DC current and an applied or residual tensile stress D - An anaerobic environment and an applied or residual tensile stress Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 3:

Although the mechanism for sulphide cracking is not completely understood, it is agreed that one of the following conditions must be present before the problem can occur:

A - Hydrogen sulphide must be present B - The steel must be completely stress-free C - Low strength steel must be involved D - There must be a total absence of water Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 4:

The factors affecting the rate of chloride stress corrosion cracking include:

A - Stress level of the metal B - Temperature to which the metal is exposed C - Oxygen content of the solution D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 5:

The type of bacteria that require oxygen to live and grow are referred to as:

A - Aerobic bacteria B - Anaerobic bacteria C - Facultative bacteria D - None of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 6:

The most destructive source of stray current corrosion is:

A - Direct current B - 220 volt current C - Alternating current D - 110 volt current Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 7:

Dry atmospheric corrosion occurs when metals have the ability to form a stable film in the presence of:

A - Carbon dioxide B - Hydrogen C - Oxygen D - Nitrogen Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 8:

In hydrogen stress cracking, the atoms of hydrogen interact with the metal to induce crack growth, which may lead to fracture. This cracking is in the absence of active corrosion. If there were active corrosion, the cracking would more correctly be termed:

A - Galvanic corrosion B - Hydrogen blistering C - Hydrogen embrittlement D - Stress corrosion cracking Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 9:

When biological corrosion occurs in an environment that is totally lacking in oxygen and high in sulphates, the most likely type of bacterial source of the corrosion is:

A - Anaerobic bacteria B - Facultative bacteria C - Aerobic bacteria D - Salmonella bacteria Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 10:

Although there are a number of environmental conditions that contribute to stress corrosion cracking, what must first exist for this condition to begin?

A - Boiler water must be raised to a pH of between 9 and 11.5 B - There must be a flaw or discontinuity in the metal C - There must be multiple layers of moisture D - A high copper-sulphate concentration must exist in the process fluid Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct

Question 1:

Gas systems have no electrolyte to carry current. The type of instrument used to measure corrosion from stack gases is called a:

A - Linear polarization meter B - Palladium foil hydrogen patch probe C - Galvanic probe D - Resistance probe Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 2:

Because a resistance probe requires no ______________ to carry current, it can be used in ___________ systems to measure corrosion from stack gases.

A - electrolyte, liquid B - wiring, gas C - wiring, liquid D - electrolyte, gas Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 3:

Fluorescent dye penetrant will indicate cracks under:

A - Visible light B - Infrared light C - Ultraviolet light D - Gamma rays Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 4:

The depth of corrosion pits is measured with a:

A - Micrometer B - Planimeter C - Galvanometer D - Vernier caliper Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 5:

A steel coupon is installed in a corrosive system and left for 45 days. The coupon is rod shaped, 100 mm long and 5 mm in diameter. Over the 45-day period, it lost a total of 0.6754 g. The density of steel is 7.861 g/mL. The corrosion rate of the coupon is:

Corrosion rate (mm/year) =

A - .043 mm/year B - 4.324 mm/year C - 43.24 mm/year D - 0.432 mm/year Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 6:

Electrical resistance probes work on the principle that:

A - As the area of a conductor increases, its resistance increases. B - As the area of a conductor decreases, its resistance decreases. C - As the area of a conductor decreases, its resistance increases. D - None of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 7:

When using radiography as an inspection tool, X-rays or gamma rays are used. The amount of radiation that passes through a metal in a given length of time is:

A - Inversely proportional to its thickness B - Influenced by the magnetic lines of force C - Directly proportional to its thickness D - Not affected by its thickness Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 8:

The instrument that is best suited for taking readings of the corrosion rate occurring on a coupon or electrode at the moment the measurement is taken is a:

A - Non-linear polarization meter B - Cross-sectional conductor C - Galvanic probe assembly D - Linear polarization meter Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 9:

The term used to describe what is happening when thin layers slough off from the metal surface is:

A - Shallow metal attack B - Blistering or scaling C - Definite surface corrosion D - Pitting or grooving Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 10:

Which of the following corrosion detecting methods uses a low viscosity, low surface tension liquid to detect cracks that extend to the surface of a metal?

A - Magnetic particle inspection B - Radiography C - Dye penetrant inspection D - Ultrasonic inspection Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct

Question 1:

The linear polarization meters are available in either two or three-electrode models. In the three-electrode model, the third electrode is used as the reference electrode and is allowed to:

A - Corrode freely B - Remain outside of the flow stream C - Be wired to ground D - Be corrected for the solution resistivity Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 2:

Pieces of metal that are inserted into a system to evaluate corrosion within a system are called:

A - Fluorocarbon gaskets B - Tubular spacers C - Coupons D - Widgets Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 3:

A steel coupon is installed in a corrosive system and left for 45 days. The coupon is rod shaped, 100 mm long and 5 mm in diameter. Over the 45-day period, it lost a total of 0.6754 g. The density of steel is 7.861 g/mL. The corrosion rate of the coupon is:

Corrosion rate (mm/year) =

A - 4.324 mm/year B - 43.24 mm/year C - 0.432 mm/year D - .043 mm/year Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 4:

Coupons are pieces of metal that are inserted into a system to evaluate:

A - System corrosiveness B - Material performance C - Inhibitor performance D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 5:

Record keeping procedures and accurate and timely reporting and recording of corrosion, damage done, and measures taken are not as important as the taking of readings from corrosion monitoring equipment.

A - True B - False Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 6:

The depth of corrosion pits is measured with a:

A - Vernier caliper B - Galvanometer C - Micrometer D - Planimeter Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 7:

When using radiography as an inspection tool, X-rays or gamma rays are used. The amount of radiation that passes through a metal in a given length of time is:

A - Inversely proportional to its thickness B - Influenced by the magnetic lines of force C - Directly proportional to its thickness D - Not affected by its thickness Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 8:

Gas systems have no electrolyte to carry current. The type of instrument used to measure corrosion from stack gases is called a:

A - Palladium foil hydrogen patch probe B - Resistance probe C - Galvanic probe D - Linear polarization meter Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 9:

The instrument that is best suited for taking readings of the corrosion rate occurring on a coupon or electrode at the moment the measurement is taken is a:

A - Cross-sectional conductor B - Non-linear polarization meter C - Linear polarization meter D - Galvanic probe assembly Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 10:

The term used to describe what is happening when thin layers slough off from the metal surface is:

A - Blistering or scaling B - Definite surface corrosion C - Pitting or grooving D - Shallow metal attack Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct

Question 1:

Electrical resistance probes work on the principle that:

A - As the area of a conductor increases, its resistance increases. B - As the area of a conductor decreases, its resistance decreases. C - As the area of a conductor decreases, its resistance increases. D - None of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 2:

When using radiography as an inspection tool, X-rays or gamma rays are used. The amount of radiation that passes through a metal in a given length of time is:

A - Inversely proportional to its thickness B - Influenced by the magnetic lines of force C - Not affected by its thickness D - Directly proportional to its thickness Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 3:

The term used to describe what is happening when thin layers slough off from the metal surface is:

A - Shallow metal attack B - Blistering or scaling C - Pitting or grooving D - Definite surface corrosion Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 4:

Fluorescent dye penetrant will indicate cracks under:

A - Visible light B - Infrared light C - Gamma rays D - Ultraviolet light Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 5:

An electric resistance probe:

A - Will detect pitting B - Cannot be used in a gas system to measure corrosion in stack gases C - Requires electrolyte to carry current D - Must be periodically removed and cleaned to remove corrosion product accumulations Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 6:

The instrument that is best suited for taking readings of the corrosion rate occurring on a coupon or electrode at the moment the measurement is taken is a:

A - Cross-sectional conductor B - Linear polarization meter C - Galvanic probe assembly D - Non-linear polarization meter Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 7:

When reporting corrosion, it is important to note the:

A - Degree of attack at a given location B - Description of the general nature and appearance of the corrosion C - Location of the corrosion D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 8:

Gas systems have no electrolyte to carry current. The type of instrument used to measure corrosion from stack gases is called a:

A - Palladium foil hydrogen patch probe B - Linear polarization meter C - Resistance probe D - Galvanic probe Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 9:

The coupon must be placed in a representative location, and oriented in such a way that it will:

A - Not be visible to the outside of the flow stream B - Induce turbulence in the flow stream C - Not induce turbulence in the flow stream D - Not contact the flow stream Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 10:

When using a slip-in rack to hold coupons, the coupon holding rod is contained in the retraction chamber, which is:

A - Flanged to the gate valve B - Mounted on the rod C - Inserted through the drain vent D - Flanged to the packing gland Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct

Question 1:

The term used to describe corrosion when the attack is deep enough to catch a knife blade is:

A - Blistering B - Definite surface corrosion C - Grooved D - Shallow metal attack Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 2:

An electric resistance probe:

A - Must be periodically removed and cleaned to remove corrosion product accumulations B - Cannot be used in a gas system to measure corrosion in stack gases C - Requires electrolyte to carry current D - Will detect pitting Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 3:

Electrical resistance probes work on the principle that:

A - As the area of a conductor increases, its resistance increases. B - As the area of a conductor decreases, its resistance decreases. C - As the area of a conductor decreases, its resistance increases. D - None of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 4:

The coupon must be placed in a representative location, and oriented in such a way that it will:

A - Not contact the flow stream B - Not induce turbulence in the flow stream C - Induce turbulence in the flow stream D - Not be visible to the outside of the flow stream Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 5:

A steel coupon is installed in a corrosive system and left for 45 days. The coupon is rod shaped, 100 mm long and 5 mm in diameter. Over the 45-day period, it lost a total of 0.6754 g. The density of steel is 7.861 g/mL. The corrosion rate of the coupon is:

Corrosion rate (mm/year) =

A - 0.432 mm/year B - .043 mm/year C - 43.24 mm/year D - 4.324 mm/year Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 6:

The instrument that is best suited for taking readings of the corrosion rate occurring on a coupon or electrode at the moment the measurement is taken is a:

A - Linear polarization meter B - Galvanic probe assembly C - Non-linear polarization meter D - Cross-sectional conductor Correctness Rule: Single Correct Answer Required Answer(s) Given: A Correct Answer(s): A Marked as: Correct _______________________________________________

Question 7:

A steel coupon is installed in a corrosive system and left for 60 days. The coupon is rod shaped, 100 mm long and 7 mm in diameter. Over the 60-day period, it lost a total of 0.8632 g. The density of steel is 7.861 g/mL. The corrosion rate of the coupon is:

Corrosion rate (mm/year) =

A - 0.585 mm/year B - 2.935 mm/year C - 0.294 mm/year D - .059 mm/year Correctness Rule: Single Correct Answer Required Answer(s) Given: C Correct Answer(s): C Marked as: Correct _______________________________________________

Question 8:

When reporting corrosion, it is important to note the:

A - Degree of attack at a given location B - Description of the general nature and appearance of the corrosion C - Location of the corrosion D - All of the above Correctness Rule: Single Correct Answer Required Answer(s) Given: D Correct Answer(s): D Marked as: Correct _______________________________________________

Question 9:

The Palladium Foil Hydrogen Patch Probe serves as a collector and catalyst for the oxidation of hydrogen that permeates through the vessel wall. The cell attached to the foil contains stainless steel electrodes in:

A - 90% mercuric acid B - 90% sulphuric acid C - 90% ammoniac acid D - 90% hydrochloric acid Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct _______________________________________________

Question 10:

Fluorescent dye penetrant will indicate cracks under:

A - Gamma rays B - Ultraviolet light C - Infrared light D - Visible light Correctness Rule: Single Correct Answer Required Answer(s) Given: B Correct Answer(s): B Marked as: Correct

Question 1: Coupons are pieces of metal that are inserted into a system to evaluate:

A - System corrosiveness B - Material performance C - Inhibitor performance D - All of the above Correct Answer(s): D Question 2: Gas systems have no electrolyte to carry current. The type of instrument used to measure corrosion from stack gases is called a:

A - Linear polarization meter B - Resistance probe C - Galvanic probe D - Palladium foil hydrogen patch probe Correct Answer(s): B Question 3:

The coupon must be placed in a representative location, and oriented in such a way that it will:

A - Not contact the flow stream B - Not induce turbulence in the flow stream C - Induce turbulence in the flow stream D - Not be visible to the outside of the flow stream Correct Answer(s): B Question 4:

When reporting corrosion, it is important to note the:

A - Degree of attack at a given location B - Description of the general nature and appearance of the corrosion C - Location of the corrosion D - All of the above Correct Answer(s): D Question 5:

Because a resistance probe requires no ______________ to carry current, it can be used in ___________ systems to measure corrosion from stack gases.

A - electrolyte, gas B - wiring, liquid C - wiring, gas D - electrolyte, liquid Correct Answer(s): A Question 6:

The instrument that is best suited for taking readings of the corrosion rate occurring on a coupon or electrode at the moment the measurement is taken is a:

A - Cross-sectional conductor B - Non-linear polarization meter C - Galvanic probe assembly D - Linear polarization meter Correct Answer(s): D Question 7:

Electrical resistance probes work on the principle that:

A - As the area of a conductor increases, its resistance increases. B - As the area of a conductor decreases, its resistance decreases. C - As the area of a conductor decreases, its resistance increases. D - None of the above Correct Answer(s): C Question 8:

The Palladium Foil Hydrogen Patch Probe serves as a collector and catalyst for the oxidation of hydrogen that permeates through the vessel wall. The cell attached to the foil contains stainless steel electrodes in:

A - 90% ammoniac acid B - 90% hydrochloric acid C - 90% mercuric acid D - 90% sulphuric acid Correct Answer(s): D Question 9:

Fluorescent dye penetrant will indicate cracks under:

A - Gamma rays B - Infrared light C - Visible light D - Ultraviolet light

Correct Answer(s): D Question 10:

Pieces of metal that are inserted into a system to evaluate corrosion within a system are called:

A - Coupons B - Widgets C - Tubular spacers D - Fluorocarbon gaskets Correct Answer(s): A