Which term means a portion of a sample removed for testing?

• A. Algae
• B. Alkalinity
• C. Baffle
• D. Aliquot

Answer: (D)

Taking a portion of a sample for testing is called an aliquot. An aliquot is a precisely measured subset that represents the whole sample, allowing analysis without using up the entire sample and helping keep results representative. In wastewater testing, you’d set aside an aliquot from a larger sample to run specific tests or to preserve material for later analysis. The other terms don’t relate to a tested portion: algae are organisms, alkalinity is a buffering capacity of water, and a baffle is a barrier used to control flow.