A sample of boiler water can be chemically...

A sample of boiler water can be chemically...

Question 1 of 270705eccefa0bacbc34ba4d46f82

A sample of boiler water can be chemically tested for alkalinity by initially adding a few drops of phenolphthalein and then slowly titrating the water sample until the __________.

Question 1 of 27070

Q

A sample of boiler water can be chemically tested for alkalinity by initially adding a few drops of phenolphthalein and then slowly titrating the water sample until the __________.

🔍 Key Concepts

• phenolphthalein indicator behavior in acid vs. base solutions • difference between color change endpoints and pH or chloride measurements • what "alkalinity" means in boiler water testing

💭 Think About

• Think about what phenolphthalein looks like in a strongly alkaline solution versus a neutral or slightly acidic solution. • Ask yourself: during a titration for alkalinity, are you usually adding acid or base to the boiler water sample? How will that affect the indicator color over time? • Consider whether alkalinity tests are designed to detect chlorides, pH to a specific number, or the point where the indicator changes appearance.

✅ Before You Answer

• Review the color transition of phenolphthalein (which color at high pH, which color at lower pH). • Confirm whether alkalinity tests are aimed at measuring chlorides or carbonate/bicarbonate/hydroxide content. • Check which option describes a distinct visible endpoint that a person in the lab could easily recognize during titration.