Molecular mass Molecular mass Relative molecular mass or molecular weight is the mass of a molecule. It is calculated as the sum of the relative atomic masses of each constituent element multiplied by the number of atoms of that element in the molecular formula. The molecular mass of small to medium size molecules, measured by mass spectrometry, determines stoichiometry. For large molecules such as proteins, methods based on viscosity and light-scattering can be used to determine molecular mass when crystallographic data are not available. Both atomic and molecular masses are usually obtained relative to the mass of the isotope C (carbon 12),
Standard weight in fish common measures of condition used in fisheries assessment and management. Fulton’s condition factor, K, is another measure of an individual fish’s health that uses standard weight. Proposed by Fulton in 1904, it assumes that the standard weight of a fish is proportional to the cube of its length: formula_2 where "W" is the whole body wet weight in grams and "L" is the length in centimeters; the factor 100 is used to bring K close to a value of one. Standard weight in fish Standard weight in fish is the typical or expected weight at a given total length for