What is used to make a pH determination—the acidity or alkalinity of water?

• A. Bacon bombs
• B. Dippers
• C. Kemmerer bottles
• D. A pH meter

Answer: (D)

Measuring pH is about quantifying how acidic or basic water is by assessing hydrogen ion activity. The direct, reliable way to get a numeric pH value is with a pH meter. It uses a glass electrode to detect hydrogen ion activity and compares it to a reference electrode, giving you an exact pH reading after proper calibration with standard buffer solutions. This can be done in the field or in a lab, with the reading being precise and repeatable when the probe is well-maintained and temperature-compensated.

The other options don’t measure pH directly: Kemmerer bottles are used to collect water samples, dippers are simple sampling tools for grabbing surface water, and bacon bombs are not instrument devices for water analysis.