Biotech Certification Complete Practice Test 2025

The correct answer is mass spectrometry because this technique specifically identifies the chemical constitution of a substance by separating ions based on their mass-to-charge ratio. In mass spectrometry, a sample is ionized, and the resulting ions are then accelerated through an electric field. As these ions travel through a magnetic field, they are separated according to their mass and charge. This separation allows for the determination of the molecular weight of the compounds present in the sample, as well as insights into their structure.

Mass spectrometry is highly sensitive and can analyze complex mixtures, providing valuable quantitative and qualitative information. It is widely used in various fields, including chemistry, pharmaceuticals, and environmental monitoring. The ability to detect and identify compounds at very low concentrations makes it an essential tool in biochemical analysis.

Other methods listed, such as chromatography, electrophoresis, and spectrophotometry, serve different purposes. Chromatography is primarily used for separation based on different physical or chemical properties of the components, electrophoresis separates molecules based on charge and size, and spectrophotometry measures the amount of light absorbed by a substance but does not identify the chemical structure directly. Thus, mass spectrometry stands out as the appropriate choice for identifying the chemical constitution by focusing on the separation of