butane
Enable an agent to identify butane, assess its composition and physical state, and determine whether a specified sample is suitable for an intended use under documented conditions.
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 butane, assess its composition and physical state, and determine whether a specified sample is suitable for an intended use under documented conditions.
Butane, in the strict chemical sense of n-butane, is the unbranched alkane CH3CH2CH2CH3, a colourless, highly flammable gas at ordinary room temperature and atmospheric pressure that can be liquefied under pressure.
It can be Resolve a sample's identity against molecular structure, identifiers and composition evidence.; Compare purity, odorization and trace contaminants with a named application specification.; Assess phase and vapor-pressure behavior using validated data within their stated ranges.; Flag ignition, pressure, liquid-contact and oxygen-displacement concerns for the recorded conditions.; Determine whether a proposed substitution or use has sufficient supporting evidence.; Request missing measurements or authoritative documentation before making a suitability decision..
Distinguishing features
A molecular formula of C4H10 distinguishes butane from propane and butenes, but does not distinguish its structural isomers.
An unbranched four-carbon skeleton identifies n-butane; a branched skeleton identifies isobutane.
A label saying 'butane' does not establish n-butane purity: composition evidence must distinguish the substance from commercial blends.
Liquid and gaseous butane are physical states of the same substance; their interpretation requires temperature and pressure.
Odor is insufficient for identification because odorants can be added and their presence varies between supplies.
Scope
+ Molecular identity and distinction between n-butane, isobutane and commercial butane mixtures
+ Sample composition, purity, grade, impurities and odorization
+ Gas or liquid state as a function of temperature, pressure and composition
+ Condition-qualified physical properties and combustion behavior
+ Substance hazards, exposure assessment and jurisdiction-specific identity
+ Suitability for a specified fuel, propellant, refrigerant or chemical-feedstock role
- Isobutane as a separately modeled chemical substance
- LPG and other formulated fuel mixtures as products
- Cylinders, valves, lighters, burners and refrigeration equipment
- Refining, separation and manufacturing processes
- Transport operations and facility emergency-response plans
Characteristics
- Chemical identity
- n-butane; isobutane; butane-containing mixture; unresolved Prevents a common name from substituting for verified molecular identity.
- Verified substance identifiers
- CAS, PubChem CID and EC records linked to the verified molecular structure Connects identity, property and regulatory evidence without mixing isomers or products.
- Composition and purity
- Component mole or mass fractions, stated basis, method and detection limits Isobutane, propane, unsaturated hydrocarbons and other constituents can change properties and suitability.
- Grade and odorization
- Supplier-defined grade; odorized, unodorized or unknown; additive identity and concentration Fuel-grade material may be unsuitable for applications requiring controlled trace impurities.
- Temperature and absolute pressure
- Temperature in K or °C; absolute pressure in Pa, kPa or bar These conditions govern phase and the applicability of measured properties.
- Phase condition
- Gas; liquid; liquid-vapor coexistence; solid; supercritical; unresolved Determines whether gas-release, liquid-contact or other state-dependent constraints apply.
- Phase-transition and vapor-pressure evidence
- Melting and boiling temperatures at stated pressures; vapor pressure versus temperature with valid range Supports assessment of vaporization and pressure behavior without treating constants as condition-free.
- Density
- kg/m³ at stated temperature, pressure, phase and composition Supports mass-volume conversion and assessment of released vapor behavior.
- Flammability and ignition properties
- Flammability limits in volume percent in a specified oxidant; ignition temperature in °C or K with test conditions Allows evaluation of ignition potential using evidence applicable to the actual conditions.
- Hazard classification
- Applicable GHS implementation, classification, physical form, jurisdiction, source and revision date Prevents classifications for another formulation or physical form from being applied automatically.
- Exposure assessment
- Butane concentration in ppm or mg/m³; oxygen in volume percent; duration and sampling location Separates substance exposure from oxygen displacement and supports comparison with applicable limits.
- Intended application specification
- Named application linked to composition, moisture, residue and operating-condition requirements Makes suitability depend on explicit requirements rather than the name 'butane' alone.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.butane
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 5 bundles · 9 layers · 16 findings · 24 questions.
Butane identity and composition Establishes what the name butane denotes and what a particular sample contains.
n-Butane, isobutane and commercial butane blends can share labeling language while requiring different property and suitability assessments.
Molecular identity
Resolves the intended molecular structure and its authoritative identity records.
Resolve the butane name
Treat the registry sense and the identity of a supplied sample as separate claims requiring evidence.
- Does vr.tr.butane denote straight-chain n-butane specifically or a broader commercial use of the word butane? boundary
- Which read authoritative records establish the structure and corresponding CAS number, PubChem CID and EC number? provenance
Sample composition
Records component fractions, additives and the evidence supporting a grade claim.
Verify purity and additives
Make the composition of the actual sample explicit before using pure-substance data or accepting a grade designation.
- What fractions of n-butane, isobutane, propane, butenes and other detected constituents are present, on what analytical basis? measurement
- Does the batch certificate establish the claimed purity, odorant content, moisture and residue limits? provenance
Butane phase and properties Connects observed physical state to composition, temperature, pressure and applicable property evidence.
Butane can be held as a liquefied gas, so pressure and temperature are essential to interpreting its state and release behavior.
Phase assessment
Establishes the current phase and whether an equilibrium interpretation is justified.
Determine phase condition
Record enough evidence to distinguish gaseous butane, liquid butane and liquid-vapor coexistence.
- What are the sample temperature, absolute pressure, composition and observed phases? measurement
- Is the sample near equilibrium, or is withdrawal, heating or depressurization changing its temperature and phase distribution? measurement
Qualified property data
Attaches conditions, uncertainty and valid ranges to phase and density data.
Select applicable property evidence
Use n-butane property values only when their identity, phase and conditions match the assessment.
- Which measured or evaluated sources support melting point, boiling point, vapor pressure and density, with units and reference conditions? provenance
- Do the proposed temperature, pressure and impurity levels lie within the source's valid range, or is mixture-specific evidence needed? boundary
Butane hazards and exposure Separates combustion, pressure, liquid-contact and inhalation concerns and connects them to applicable evidence.
A butane assessment must account for both its flammability and the consequences of storing or releasing a volatile substance.
Ignition and release
Assesses flammable atmospheres and state-dependent consequences of a release.
Assess release conditions
Judge a potential release using the recorded physical state, surroundings and validated hazard data.
- Which sources establish applicable flammability limits and ignition properties, including oxidant and test conditions? provenance
- Could the specified release produce a flammable atmosphere, vapor accumulation or contact with rapidly evaporating liquid? action
Exposure and classification
Records exposure evidence and classification applicable to the substance or actual supplied composition.
Match hazard evidence to sample
Keep exposure limits, oxygen measurements and classification tied to their jurisdiction, physical form and composition.
- Which current authoritative sources establish the applicable GHS classification and occupational exposure limits, including averaging periods and any impurity-dependent provisions? provenance
- What butane and oxygen concentrations were measured, where, for how long and with which instrument limitations? measurement
Butane use suitability Evaluates whether a verified sample can meet a specified application's material and operating requirements.
Butane suitable as a fuel is not automatically suitable as a refrigerant, propellant or chemical feedstock.
Application grade
Connects composition and grade evidence to an explicitly named use.
Compare sample with use requirements
Make suitability a comparison between documented sample properties and a documented application specification.
- What n-butane purity, isomer content, moisture, sulfur-containing additives and nonvolatile residue limits does the intended use require? definition
- Does the available batch evidence demonstrate compliance, or which additional analysis is needed? action
Substitution and system interface
Identifies where substance-level suitability depends on an equipment or product model.
Qualify proposed substitution
Do not infer interchangeability between n-butane, isobutane, propane or their blends from their shared hydrocarbon identity.
- How would the proposed substitution change vapor pressure, phase behavior, combustion requirements or application performance under the specified conditions? measurement
- Which equipment compatibility, operating-envelope and product-approval requirements must the neighboring system model establish before use? boundary
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.
- This description uses the strict n-butane sense; the registry should confirm whether the intended scope includes both C4H10 isomers or commercial butane fuel.
- Identifiers and approximate physical constants are recalled, not verified against sources in this response.
- Exact hazard categories, exposure limits, transport entries and purity-dependent regulatory conditions require jurisdiction-specific verification.
- Which of these check these first hold for the sense of butane 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 - 106-97-8 - Identifies n-butane, not isobutane or a commercial fuel mixture.
- PubChem CID - 7843 - Compound identifier for n-butane.
- EC number - 203-448-7 - European chemical inventory identifier for n-butane.
- Molecular formula - C4H10 - Shared by n-butane and its constitutional isomer, isobutane; insufficient alone to distinguish them.
- Which of these identifiers and schemes hold for the sense of butane this model covers, and on what evidence? provenance
Standards and regulation
Recalled without web access and unsourced; every item is a lead to verify.
- United Nations Globally Harmonized System of Classification and Labelling of Chemicals (GHS): framework for communicating flammability and gas-under-pressure hazards.
- European Union Classification, Labelling and Packaging Regulation (CLP): governs substance and mixture classification, labelling and packaging in the EU.
- United Nations Recommendations on the Transport of Dangerous Goods, Model Regulations: provide the international framework for dangerous-goods transport classification.
- Which of these standards and regulation hold for the sense of butane this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Fuel in lighters and portable cooking equipment.
- Component of liquefied petroleum gas (LPG).
- Propellant in aerosol products.
- Petrochemical feedstock for producing other chemicals, including maleic anhydride.
- Refrigerant designated R-600 in equipment designed for flammable refrigerants.
- Which of these real-world use hold for the sense of butane 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 - 58.12 - g/mol
- Normal boiling point of pure n-butane at 101.325 kPa - approximately -0.5 - °C
- Melting point of pure n-butane - approximately -138.3 - °C
- Which of these typical measurements hold for the sense of butane 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.
- Leaks can form readily ignitable mixtures with air; ignition in confined spaces can cause explosions.
- Vapour is denser than air and can accumulate in low areas or travel to an ignition source.
- High concentrations can displace oxygen and cause asphyxiation; inhalation can also depress the central nervous system.
- Contact with rapidly evaporating liquid can cause cold burns or frostbite.
- Heating a pressurised container can cause rupture; incomplete combustion can produce carbon monoxide.
- Which of these failure modes and hazards hold for the sense of butane this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Commercial products sold as butane may contain isobutane, propane or other hydrocarbons; composition and purity require product-specific confirmation.
- LPG formulations vary by market and season, partly because n-butane vaporises poorly in cold conditions.
- Workplace exposure limits and legally required hazard communication vary by jurisdiction.
- Which of these regional variation hold for the sense of butane 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.
- isobutane - Has the same molecular formula but a branched carbon skeleton; its systematic name is 2-methylpropane.
- propane - Has three carbon atoms and formula C3H8, with a substantially lower normal boiling point.
- liquefied petroleum gas - Is a commercial class of hydrocarbon fuels, commonly mixtures containing propane and butanes, rather than a single pure compound.
- butene - Contains a carbon-carbon double bond and has formula C4H8, whereas butane is saturated.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of butane this model covers, and on what evidence? provenance
What the second pass must settle
- Does the registry's underlying identity record establish n-butane specifically, or must its scope accommodate a broader butane sense?
- Which authoritative identity records and evaluated property sources should anchor the identifiers, constants and temperature-dependent data?
- Which grade specifications are relevant to the intended applications, and how do they constrain isomer content, odorants, moisture and residue?
- Which jurisdictions and supplied compositions determine the applicable hazard classifications and exposure limits, including impurity-dependent provisions?
- Does an existing Vercy world model already own this chemical concept, requiring a registry link rather than a separate publication?