What instrument is used to measure relative abundance?

The instrument commonly used to measure relative abundance is a mass spectrometer. It analyzes the mass-to-charge ratio of ions to identify and quantify different isotopes or molecules in a sample. By generating a spectrum that displays the abundance of each detected species, it allows researchers to determine their relative abundances effectively. Other techniques, such as chromatography combined with detectors, can also be used for similar purposes in specific contexts.