🔍 Key Concepts

• Boiler water chemistry and why we control alkalinity • Difference between corrosion problems and deposition/scale problems • Specific meaning of caustic embrittlement in marine boilers

💭 Think About

• Which of these choices is a direct result of water being too alkaline (too caustic), as opposed to just having hardness or oxygen present? • Look at each option and ask: does this describe a cracking/metal damage problem, a reaction with oxygen, or a hardness/scale issue? • Think about which problem is specifically associated with very high concentrations of caustic (sodium hydroxide) at stressed areas of boiler metal.

✅ Before You Answer

• Identify which options are mainly related to water hardness (calcium, scale) rather than alkalinity itself. • Identify which option involves dissolved oxygen control chemicals instead of alkalinity. • Recall the definition of embrittlement and whether high causticity can cause this type of metal failure.