Mole

high-resolution terminology - matching measurements at high-resolution

Mole

Description

The mole [mol] is the SI base unit for the amount of substance of a system that contains 6.02214076·10²³ specified elementary entities (see Avogadro constant). The elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.

Abbreviation: mol

Reference: Bureau International des Poids et Mesures 2019 The International System of Units (SI), Gnaiger MitoFit Preprints 2020.4

The redefined international system of units

Since 2019-05-20, the definition of the mole is (from EURAMET):

The mole, symbol mol, is the SI unit of amount of substance. One mole contains exactly 6.022 140 76 × 10²³ elementary entities. This number is the fixed numerical value of the Avogadro constant, N_A, when expressed in the unit mol⁻¹ and is called the Avogadro number.

The amount of substance, symbol n, of a system is a measure of the number of specified elementary entities. An elementary entity may be an atom, a molecule, an ion, an electron, any other particle or specified group of particles.

From 1971 until 2019-05-20, the definition of the mole has been:

1. The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilograms of carbon 12; its symbol is "mol".
2. When the mole is used, the elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.

Quantity	Symbol for quantity Q	Symbol for dimension	Name of abstract unit uQ	Symbol for unit uQ [*]
elementary entity *,$	UX	U	elementary unit	x
count *,$	NX = N·UX	X	elementary unit	x
amount of substance *,§	nX = NX·NA-1	N	mole	mol
charge *,€	Qel = zX·e·NX	I·T	coulomb	C = A·s
length	l	L	meter	m
mass	m	M	kilogram	kg
time	t	T	second	s
electric current	I	I	ampere	A
thermodynamic temperature	T	Θ	kelvin	K
luminous intensity	Iv	J	candela	cd

[*] SI units, except for the canonical 'elementary unit' [x]. The following footnotes are canonical comments, related to iconic symbols.

^* For the elementary quantities N_X, n_X, and Q_el, the entity-type X of the elementary entity U_X has to be specified in the text and indicated by a subscript: n_O2; N_ce; Q_el.

^$ Count N_X equals the number of elementary entities U_X. In the SI, the quantity 'count' is explicitly considered as an exception: "Each of the seven base quantities used in the SI is regarded as having its own dimension. .. All other quantities, with the exception of counts, are derived quantities" (Bureau International des Poids et Mesures 2019 The International System of Units (SI)). An elementary entity U_X is a material unit, it is not a count (U_X is not a number of U_X). N_X has the dimension X of a count and U_X has the dimension U of an elementary entity; both quantities have the same abstract unit, the 'elementary unit' [x].

^§ Amount n_X is an elementary quantity, converting the elementary unit [x] into the SI base unit mole [mol] using the Avogadro constant N_A.

^€ Charge is a derived SI quantity. Charge is an elementary quantity, converting the elementary unit [x] into coulombs [C] using the elementary charge e, or converting moles [mol] into coulombs [C] using the Faraday constant F. z_X is the charge number per elementary entity U_X, which is a constant for any defined elementary entity U_X. Q_el = z_X·F·n_X

Bioblast links: SI base units - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>

Entity, count, and number, and SI base quantities / SI base units

Quantity name	Symbol	Unit name	Symbol	Comment
elementary	UX	elementary unit	[x]	UX, UB; [x] not in SI
count	NX	elementary unit	[x]	NX, NB; [x] not in SI
number	N	-	dimensionless	= NX·UX-1
amount of substance	nB	mole	[mol]	nX, nB
electric current	I	ampere	[A]	A = C·s-1
time	t	second	[s]
length	l	meter	[m]	SI: metre
mass	m	kilogram	[kg]
thermodynamic temperature	T	kelvin	[K]
luminous intensity	IV	candela	[cd]

Fundamental relationships

» Avogadro constant N_A

» Boltzmann constant k

» elementary charge e

» Faraday constant F

» gas constant R

» electrochemical constant f

SI and related concepts

» International System of Units

» elementary unit x

» SI prefixes

» International Union of Pure and Applied Chemistry, IUPAC

» entity

» quantity

» dimension

» format

» motive unit

» iconic symbols

Bioblast links: Concentration and pressure - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>

Concentration

» Volume

» Activity

» Concentration

» Density

» Mole

» Molar mass

Pressure

» Barometric pressure

» Chemiosmotic pressure

» Gas pressure

» Osmotic pressure

» Oxygen pressure

» pascal

» Pressure

Solubility = concentration/pressure

» Solubility

» Solubility factor

» Oxygen solubility

General

» Boltzmann constant

» Energy

» Force

» Gas constant

» Work

Related keyword lists

» Keywords: Oxygen signal

» Keywords: Normalization

MitoPedia concepts: Ergodynamics