alum
Enable an agent to identify material registered as alum, assess its composition and condition, and determine its suitability for a specified use.
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.
recalled by Codex without web access - no source was read
Researched by: Codex
Purpose and description
Enable an agent to identify material registered as alum, assess its composition and condition, and determine its suitability for a specified use.
Alum denotes a family of hydrated double sulfates, typically with formula M⁺M³⁺(SO₄)₂·12H₂O, and commonly means potassium aluminium sulfate dodecahydrate, KAl(SO₄)₂·12H₂O.
It can be Resolve an alum label to a supported chemical identity or flag it as ambiguous.; Compare batches after normalising assay and hydration bases.; Select material against application-specific purity and grade requirements.; Calculate preparation quantities using verified composition and concentration basis.; Investigate caking, incomplete dissolution or changed hydration before releasing material for use.; Retrieve handling and disposal requirements tied to the identified species and jurisdiction..
Distinguishing features
Determine the constituent cations and sulfate stoichiometry instead of identifying alum from its trade name or appearance.
Distinguish potassium alum from other declared alum species by identifying the counterion.
Distinguish hydrated material from anhydrous or dehydrated material before assigning identifiers or comparing mass-based assays.
Check whether a product labelled alum contains a double sulfate, aluminium sulfate alone, or a formulation requiring a neighbouring material model.
Require compositional evidence to distinguish an alum substance from a product containing alum.
Scope
+ Chemical interpretation of the name alum, including constituent ions and hydration state
+ Species-specific identifiers and evidence connecting them to the material
+ Grade, assay basis, impurities and batch variability
+ Solid condition, dissolution behaviour and aqueous preparation properties
+ Suitability, handling constraints and regulatory identity for a specified application
- Finished deodorant blocks, styptic products and other formulations containing alum
- Design and operation of water-treatment or textile-dyeing processes
- Manufacturing equipment and complete alum production workflows
- Clinical efficacy and treatment decisions
- Geological deposits and mineral extraction systems
Characteristics
- Resolved alum species
- Declared chemical name, constituent ions and formula; unresolved permitted The word alum alone cannot establish which material properties and restrictions apply.
- Hydration state
- Moles of water per formula unit; measured, declared or unresolved Hydration affects formula mass, assay interpretation and thermal behaviour.
- Chemical identifier mapping
- CAS number, PubChem CID and EC number linked to a specific species and hydration state Prevents records for different chemical forms from being combined.
- Assay and reporting basis
- % by mass as named hydrate, anhydrous salt, aluminium or another explicitly defined basis Numerically similar assays may represent different amounts of usable material.
- Grade and conformity
- Supplier grade plus named specification, edition and conformity evidence A grade label must be connected to actual acceptance criteria.
- Impurity profile
- mg/kg or % by mass for specified analytes, with method and detection limits Trace constituents and insoluble matter may control application suitability.
- Physical presentation
- Crystals, powder, dehydrated material or identified aqueous preparation; particle size in µm or mm where relevant Presentation affects sampling, dissolution and handling.
- Aqueous concentration and pH
- g/L or mol/L on a declared basis; pH at specified concentration and temperature Solution measurements cannot be interpreted without preparation conditions.
- Solubility
- g solute per 100 g water at stated °C, with species and hydrate basis Supports preparation decisions and interpretation of residual solids.
- Thermal transitions
- °C with method, pressure and event assignment: melting, dehydration or decomposition A reported thermal event must not automatically be treated as a melting or boiling point.
- Applicable hazard and exposure record
- Species-specific SDS, jurisdiction, revision, GHS classification and applicable exposure limits with units Handling decisions require evidence applicable to the actual material.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.alum-artifact
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 35 questions.
Alum identity and naming boundaries Resolve what the registry name and each supplied material actually denote.
An unresolved alum name can attach the wrong formula, identifiers or use constraints to a material.
Registry sense
Establish the intended chemical breadth of this entry.
Species or family
Treat potassium alum as a candidate interpretation, not a settled registry definition. PubChem describes potassium alum as potassium aluminium sulfate, predominantly in dodecahydrate form. [PubChem potassium alum](https://pubchem.ncbi.nlm.nih.gov/compound/potassium%20aluminum%20sulfate)
- Does the originating registry record identify potassium alum specifically or a broader alum class? definition
- Which upstream identifier or source establishes that intended meaning? provenance
Material name resolution
Connect labels to chemical evidence and neighbouring entries.
Label-to-composition match
Require a supported species assignment before treating a commercial alum label as chemically precise.
- Which cations, sulfate ratio and hydration state are supported by the label, certificate or analysis? measurement
- Does this material belong here, or is it aluminium sulfate or an alum-containing formulation? boundary
- Does an existing world model already own the resolved concept? boundary
Composition, hydration and assay Establish what a measured quantity of alum contains.
Hydrate water and differing assay conventions can make nominally comparable quantities chemically unequal.
Hydrate accounting
Connect chemical formula, water content and identifier selection.
Verified hydrate form
Record the actual hydrate explicitly; PubChem maintains a separate record for aluminium potassium sulfate dodecahydrate. [PubChem dodecahydrate](https://pubchem.ncbi.nlm.nih.gov/compound/Aluminum%20potassium%20sulfate%20dodecahydrate)
- What hydration state is declared, and what measurement supports it? measurement
- Do the assigned CAS, EC and PubChem identifiers describe that same chemical form? boundary
Assay comparability
Make purity and dose calculations interpretable.
Declared assay basis
Keep analytical result, calculation basis and uncertainty together.
- Is the assay expressed as hydrated salt, dried salt, aluminium content or another basis? definition
- Which analytical method, sample conditioning and uncertainty accompany the result? measurement
- What conversion is justified before comparing this batch with another alum grade? action
Alum grade and impurities Determine whether the batch meets the compositional requirements of its intended use.
Chemical identity alone does not establish acceptable impurity levels or grade conformity.
Grade evidence
Translate supplier grade claims into inspectable requirements.
Specification conformity
Associate a grade with its named specification and batch-specific evidence.
- Which specification and edition define this alum grade? provenance
- Which required tests have passing results for the supplied batch? measurement
Impurity discrimination
Identify constituents that affect the proposed use.
Use-limiting constituents
Record relevant trace elements, residual salts and insoluble matter without assuming a universal impurity specification.
- Which impurities and insoluble residues must be measured for this application? measurement
- Are the analytical detection limits low enough to demonstrate compliance with the selected specification? measurement
- Should missing or failing impurity results prevent release for the proposed use? action
Physical and aqueous state Describe alum as received and after preparation in water.
Crystal condition, hydration history and preparation conditions affect whether a batch behaves as expected.
Solid condition
Track observations and changes affecting solid alum.
Storage and thermal history
Interpret caking, water content and thermal events using the identified chemical form.
- What particle size, caking, moisture and appearance changes are observed? measurement
- What storage or heating history could have changed the material's hydration state? provenance
- Does each reported thermal constant represent melting, dehydration or decomposition, and is a boiling point meaningful? definition
Aqueous preparation
Describe the conditions under which alum is dissolved and evaluated.
Solution condition evidence
Tie dissolution, pH and residual solids to an explicit preparation protocol.
- What concentration basis, water composition and temperature define the preparation? measurement
- What pH, dissolution time and residual solids are measured under those conditions? measurement
- Does incomplete dissolution require dilution, additional characterisation or batch rejection? action
Use and handling constraints Connect identified alum material to justified application and handling decisions.
A familiar substance name does not establish suitability, permission or handling requirements for a particular use.
Application qualification
Assess the material requirements of a proposed role.
Role-specific acceptance
Evaluate proposed roles such as mordant, treatment reagent or formulation ingredient against evidence for the actual species and grade.
- What chemical role is proposed, and which species, grade and impurity limits does it require? definition
- What application test supports acceptance of this batch? measurement
- Which performance or formulation decisions belong to the neighbouring process or product model? boundary
Hazard and regulatory fit
Resolve handling and legal requirements for the actual material and context.
Applicable material requirements
Require current, attributable requirements instead of transferring classifications between alum species or products.
- Which current SDS and jurisdictional records match this species, hydration state and supplied form? provenance
- What GHS classification and exposure limits apply, including units and averaging periods, and which are unestablished? measurement
- What handling, storage and disposal actions follow for the intended quantity and use? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- No sense is recorded: confirm whether the registry means the alum family, potassium alum specifically, or commercial water-treatment alum.
- The identifier and molar mass supplied here apply specifically to potassium alum dodecahydrate.
- Verify grade-specific purity requirements, hazard classifications, permitted uses, and thermal or solubility data for the exact compound and hydration state.
- Which of these check these first hold for the sense of alum this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Potassium alum
- Ammonium alum
- Sodium alum
- Chrome alum (potassium chromium(III) sulfate dodecahydrate)
- Which of these kinds and varieties hold for the sense of alum this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- CAS Registry Number - 7784-24-9 - Identifies potassium aluminium sulfate dodecahydrate, not the entire alum family or its anhydrous counterpart.
- Chemical formula - KAl(SO₄)₂·12H₂O - Formula of potassium alum; other alums substitute the monovalent or trivalent cation.
- Which of these identifiers and schemes hold for the sense of alum this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Potassium and ammonium alums are used as mordants in dyeing.
- Potassium alum is used in styptic and astringent products.
- Potassium alum is used for growing demonstration crystals.
- Aluminium-containing alums can serve as coagulants in water clarification.
- Chrome alum is used in leather tanning.
- Which of these real-world use hold for the sense of alum this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Molar mass of potassium alum dodecahydrate - 474.39 - g/mol
- Water of crystallization in the ideal alum formula - 12 - mol H₂O per mol of formula units
- Which of these typical measurements hold for the sense of alum this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Dust or solutions can irritate eyes, skin, or respiratory passages; effects depend on composition and concentration.
- Heating can remove water of crystallization and change the material's phase and properties.
- Incorrect coagulant dosing can alter water pH and leave undesirable residual aluminium.
- Industrial material may contain impurities that make it unsuitable for food, cosmetic, or pharmaceutical applications.
- Hazard information for aluminium alums cannot be transferred directly to chromium-containing alums.
- Which of these failure modes and hazards hold for the sense of alum this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- In water-treatment trade usage, 'alum' often means aluminium sulfate rather than a double sulfate; a supplier's formula and specification establish the identity.
- Which of these regional variation hold for the sense of alum this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Aluminium sulfate - Al₂(SO₄)₃ lacks the additional monovalent cation required by the conventional alum double-sulfate formula, although it is commercially called alum.
- Alumina - Alumina is aluminium oxide, Al₂O₃, rather than a hydrated sulfate salt.
- Aluminium hydroxide - Al(OH)₃ is a hydroxide rather than an alum; vaccine-adjuvant usage of 'alum' may encompass aluminium hydroxide or phosphate preparations.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of alum this model covers, and on what evidence? provenance
What the second pass must settle
- Does vr.tr.alum denote potassium alum specifically, aluminium-containing alums, or the broader structural family of alum salts?
- Does an existing world model already cover the intended concept, requiring this registry entry to link to it?
- How should commercial uses of alum for aluminium sulfate and dehydrated products be mapped without silently widening this entry?
- Which species-specific identifiers, thermophysical measurements and grade specifications should be adopted as authoritative?
- Which intended applications and jurisdictions determine the relevant impurity limits, hazard classifications and use restrictions?