Carbon-12 Carbon-12 Carbon-12 (C) is the more abundant of the two stable isotopes of carbon (Carbon-13 being the other), amounting to 98.93% of the element carbon; its abundance is due to the triple-alpha process by which it is created in stars. Carbon-12 is of particular importance in its use as the standard from which atomic masses of all nuclides are measured, thus, its atomic mass is exactly 12 daltons by definition. Its nucleus contains 6 protons and 6 neutrons. Before 1959 both the IUPAP and IUPAC used oxygen to define the mole; the chemists defining the mole as the number of
Standard weight in fish relationships representing a species across its range are used. As fish grow in length, they increase in weight. The relationship between weight and length is not linear. The relationship between length ("L") and weight ("W") can be expressed as: When the equation is for standard weight, the standard weight for a given length is written as W. The exponent "b" is close to 3.0 for most species. The coefficient "a" varies between species. If the exponent "b" is greater than three for a certain fish species, that species tends to become relatively fatter or have more girth as it grows