← Back to catalogue
Research draft

amount of substance

vr.tr.amount-of-substance · XCT.QLT

Let an agent explain amount of substance and the mole, relay definitions and usage from metrology and chemistry references, describe calculations with molar mass and concentration, and distinguish amount of substance from mass, number and dose quantities.

Thing Registry Cross-cutting context

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify

Researched by: Claude

Purpose and description

Let an agent explain amount of substance and the mole, relay definitions and usage from metrology and chemistry references, describe calculations with molar mass and concentration, and distinguish amount of substance from mass, number and dose quantities.

A base quantity of the International System of Units that measures the number of specified elementary entities such as atoms, molecules or ions in a sample, with the mole as its unit defined since 2019 as exactly 6.02214076 times ten to the twenty-third entities, used in chemistry to relate mass to numbers of particles through molar mass and in forms such as the amount of a component, initial and equilibrium amounts in reactions and trace quantities; the registry aliases absorbed dose and lethal dose belong to other quantities.

What it is for: Counting entities in chemistry.

It can be explain the quantity and mole; relay definitions and usage; describe calculations; distinguish from other quantities.

Distinguishing features

Counts entities

SI base quantity

Exact Avogadro definition

Chemical calculations

What it looks like

Not a visible object; a quantity in equations.

Physical character

SI unit: mole unit - symbol mol

Avogadro constant: 6.02214076e23 per mole - exact since 2019

molar mass of carbon-12: about 12 g/mol - no longer exactly 12

How it is recognised

SI base quantity counting entities

Mole, molar mass, amount of component, initial and equilibrium amounts, trace quantities

Mass is measured in kilograms; absorbed dose is energy per mass; lethal dose is a toxicology measure

Related models

is a kind of - in registry terms

extensive quantity

is a kind of - in registry terms

scalar quantity

is measured in - the SI unit

mole

is related to mass by - of the substance

molar mass

In practice

Families and kinds

amount of substance of a pure sample

amount of substance of a component in a mixture

initial and equilibrium amounts in reactions

trace quantities

amount concentration and molality as derived quantities

Identifiers

ISO 80000-9 amount of substance physical chemistry quantities

SI mol base unit

Standards and regulation

SI Brochure and 2019 redefinition

ISO 80000-9

IUPAC Green Book

Failure modes and hazards

Confusing amount of substance with mass or number

Registry aliases mixing in dose quantities

Ambiguity about which entity is counted

Also called

absolute lethal doseamount of substance of componentequilibrium amount of substanceinitial amount of substanceabsorbed dosetrace quantityto tastebody burdenamount of osmotically active particles

Where this came from

wikidata · CC0 1.0

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.

Understand What amount of substance is.

Science.

Definition

Definition and the mole.

Definition

Definition.

  1. What is amount of substance, and how is the mole defined since 2019? definition
  2. Is the question about amount of substance, mass, number of entities or a dose quantity? boundary

Forms

Forms of the quantity.

Forms

Forms.

  1. What are the amount of a component, initial and equilibrium amounts, and trace quantities? definition
  2. Which entry fits the specific form? action
Compute Calculations.

Practice.

Molar

Molar mass and concentration.

Molar

Molar.

  1. How are amount, mass, molar mass and concentration related in calculations? action
  2. Which references are standard? provenance

Stoichiometry

Stoichiometry.

Stoichiometry

Stoichiometry.

  1. How is amount of substance used in reaction stoichiometry and equilibrium calculations? action
  2. Which entry fits stoichiometry? action
Measure Measurement.

Science.

Realisation

Realising the mole.

Realisation

Realisation.

  1. How is the mole realised in practice, and what was the Avogadro project? provenance
  2. Which sources are cited? provenance

History

History of the mole.

History

History.

  1. How did the mole develop from Avogadro and Ostwald to the 2019 redefinition? provenance
  2. Which entry fits the history of the mole? action
Context Teaching and related quantities.

Context.

Teaching

Teaching.

Teaching

Teaching.

  1. How is the mole taught, and what misconceptions arise? provenance
  2. Which entry fits chemistry education? action

Related

Dose quantities.

Related

Related.

  1. What are absorbed dose and lethal dose, and why are they distinct from amount of substance? provenance
  2. Which entry fits absorbed dose? action

What the second pass must settle

  • Should the mole be the primary linked entry?
  • How should metrology references be linked?
  • The registry entry has merged aliases naming dose quantities; should they be corrected?