California Wastewater Treatment Operator Practice Exam

Which analytical technique is commonly used in wastewater testing?

1. Magnetic resonance imaging

2. Electrophoresis

3. Spectrophotometry

4. Mass spectrometry only

The correct answer is: Spectrophotometry

Spectrophotometry is commonly used in wastewater testing because it allows for the measurement of the intensity of light absorbed or transmitted by a sample. This technique is particularly useful for determining the concentration of various contaminants, such as nutrients, organic compounds, and pathogens in wastewater, based on their characteristic absorbance at specific wavelengths. By using a spectrophotometer, operators can quickly and effectively analyze samples to ensure compliance with regulatory standards and assess the efficiency of treatment processes. Its versatility and efficiency make it a preferred method in the wastewater industry. While other techniques like electrophoresis and mass spectrometry have their applications in analytical chemistry, they are less frequently used in routine wastewater testing due to their complexity, cost, and the nature of the analyses required. Electrophoresis is more suitable for separating and analyzing macromolecules, and mass spectrometry, while highly sensitive, often requires extensive sample preparation and is typically used for more advanced or specific analysis rather than for standard wastewater assessments.