Questions with Complete Solutions

Power Engineering 3B1 Chapter 10 Questions with Complete Solutions (Latest 2025) Which of the following is caused from scale buildup on

boiler tubes:

• Increased boiler efficiency
• Weakening of tube metal
• Decreased boiler efficiency
• Increased flue gas temperature
• Cracks in boiler tubes
• 1,2,3,4
• 1,3,4,5
• 2,3,4,5
• 1,2,4,5
• 1,2,3,5 - Correct Answers ✅c. 2,3,4,5

When adding phosphate to the boiler water, the chemical

may:

• Combine with dissolved solids in the boiler water
• Decrease the dissolved solids in the boiler water
• Increase the suspended solids in the boiler water 1 / 3

Power Engineering 3B1 Chapter 10 Questions with Complete Solutions (Latest 2025)

• Increase the pH of the boiler water
• 1,2,3
• 1,2,4
• 1,3,4
• 2,3,4
• 1,2,3,4 - Correct Answers ✅c. 1,3,4

Chelating agents fed to the boiler water:

• Require close control to prevent corrosion
• Reduce scale build up within high-pressure boilers
• Protects against corrosion within the boiler
• Obtains best results with soft water
• 1,2,3
• 1,2,4
• 1,3,4
• 2,3,4
• 1,2,3,4 - Correct Answers ✅b. 1,2,4 2 / 3

Power Engineering 3B1 Chapter 10 Questions with Complete Solutions (Latest 2025) Organics, such as tannins, lignins and starches are used

to:

• Control silica in boiler water
• Reduce corrosion within the boiler
• Coat suspended solids in the boiler water
• Produce a non-sticky sludge in the boiler water
• 1,2,3
• 1,3,4
• 1,2,4
• 2,3,4
• 1,2,3,4 - Correct Answers ✅b. 1,3,4

To reduce scale and mud formation within the boiler, we:

• Force the hardness in the water to come out of solution

by feeding sulphite to the boiler water

• Treat the suspended solids in the boiler water with

lignins

• Remove suspended solids from the boiler water

through blow off

• / 3