The mass of one mole of a substance in grams equals its atomic or molecular mass due to the definition of the Avogadro constant
the verdict
SUPPORTED
the evidence backs this
refutedsupported
the weight of evidence
2 sources for · 0 against
The literature confirms that the mole's definition ties the mass of a substance in grams to its relative atomic or molecular mass because Avogadro's number equals the gram-to-dalton mass ratio.
Abstract The International System of Units’ (SI) base unit of the quantity “amount of substance” is the mole (symbol: mol). After the revision of the SI to be implemented in 2019, when all SI units will be based solely on constants, the mole will be defined through a fixed value of the Avogadro constant N A . One mole contains exactly 6.02214076 × 10 23 elementary entities, meaning the mole will no longer be linked to the kilogram. Currently, the mole is defined via the mass of exactly 0.012 kg of the 12 C isotope which links it to the kilogram prototype. The history, changes, and implications of the revised definition of the mole are discussed here from the chemist's point of view. The ability to count entities such as atoms or molecules (precisely enough to enable a revision of the SI and preserve consistency of previous and future measurements) is crucial. This is achieved with the realization ( Mise en Pratique ) based on the X‐ray‐crystal density (XRCD) method (counting the atoms in a silicon sphere). The determination of N A , focusing on the measurement of the molar mass of silicon highly enriched in the 28 Si isotope, with the lowest uncertainty so far, is presented.
The fundamental concept of the mole stems from the idea of the gram-atom (or gram-molecule): that an amount of one mole of a given substance has an associated mass, in grams, numerically exactly equal to the relative atomic (or molecular) mass of the substance. This means that the particular number of entities comprising one mole, Avogadro’s number, must be exactly equal to the gram-to-dalton mass ratio. Various interpretations of what a mole actually means and how this affects the ideal gas equation depend on how the amount of a given substance, n, is related to the corresponding number of entities, N. We look at three alternatives: (1) the conventional interpretation in which n is directly proportional to N, where the proportionality factor is the reciprocal of the (evidently poorly understood) Avogadro constant; (2) a more easily comprehended alternative in which n is equal to N entities; and (3) an interpretation in which n and N both represent the number of entities, but expressed in different ways. Regardless of these different interpretations, the form of the stoichiometric equations (relating N, n and the total sample mass) and the form of the relationship between the universal gas constant and the Boltzmann constant remain the same.
Everything we examined (2)
This check searched the claim as stated. It did not run a separate search for evidence against it.