Argon-39
Also known as Ar-39 radioisotope, 39Ar radioisotope, Argon, isotope of mass 39
Key facts
What buyers check first
- CAS number
- 25729-41-3
- Formula
- Ar
- Molar mass
- 38.96 g/mol
- Physical form
- Gas
- HS code
- 284443
- Category
- Metals, alloys and elements

What is Argon-39?
Plain description, key identifiers and synonyms
Argon-39 atom is a trace radioisotope of argon with atomic mass of 38.964313 and a half-life of 269 years. It has a role as an isotopic tracer.
Identifiers
Registry numbers, names and line notations, tap to copy
- IUPAC name
- argon-39
- CAS number
- 25729-41-3
- Molecular formula
- Ar
- InChIKey
- XKRFYHLGVUSROY-BJUDXGSMSA-N
- InChI
- InChI=1S/Ar/i1-1
- Canonical SMILES
- [Ar]
- Isomeric SMILES
- [39Ar]
Synonyms
- Ar-39 radioisotope
- 39Ar radioisotope
- Argon, isotope of mass 39
- 39Ar
- 39Ar isotope
- argon-39 atom
- Argon-39 isotope
- Isotope:39Ar
- Isotope:Argon-39
- argon 39
- 39Ar (isotope)
- (39)Ar radioisotope
- (39)Ar
- (39)18Ar
Physical and chemical properties
Measured values and descriptors computed from the structure
Physical and chemical properties
Measured values, check the supplier specification for your grade
| Physical form | Gasexp.Measured value |
|---|
Values vary by grade. Ask suppliers for the COA or TDS of the batch you buy.
Computed descriptors
Calculated from the structure, useful for screening and formulation
| Molecular weight | 38.96 g/molcalc.Computed value |
|---|---|
| Exact mass | 38.9643 Dacalc.Computed value |
| LogP (octanol/water) | 0calc.Computed value |
| Topological polar surface area | 0 Ųcalc.Computed value |
| Hydrogen bond donors | 0calc.Computed value |
| Hydrogen bond acceptors | 0calc.Computed value |
| Rotatable bonds | 0calc.Computed value |
| Heavy atoms | 1calc.Computed value |
| Rings | 0calc.Computed value |
| Aromatic rings | 0calc.Computed value |
| Fraction sp3 carbons | 0calc.Computed value |
| Formal charge | 0calc.Computed value |
| Stereocentres | 0calc.Computed value |
Calculated for screening. Confirm critical figures with the supplier.
Safety and hazards
GHS classification summary, not a safety data sheet
No GHS hazard classification is recorded for this substance yet. That does not mean it is harmless.
GHS classification summary, not a safety data sheet (SDS). Classifications can differ by supplier, grade and concentration. Always check the supplier's SDS.
Argon-39 suppliers
Sponsored listings first, then the documented ranking: membership, verification, replies, completeness, freshness and ratings
Post one free request and suppliers who make or trade Argon-39 can send you quotes. Your contact details stay private until you accept a quote.
Argon-39 price
Indicative price range per kg from live supplier offers
Suppliers quote this chemical on request. Send one free request and compare quotes side by side.
Uses and applications
What the substance is used for, by industry and function
Industries and functions
Roles
- isotopic tracer
- tracer
Regulatory status
Inventories, regulations and trade controls that list this substance
No regulatory list memberships are recorded for this substance yet. Always check the rules of the importing and exporting country before trade.
HS code and trade data
Customs classification and reported world trade statistics
Global trade
World import and export statistics for the HS code Argon-39 is traded under.
Radioactive elements and isotopes and compounds other than those of subheading 284410…
- Canada32.1%
- Netherlands17.0%
- Germany11.4%
- United States37.8%
- Germany8.4%
- China5.8%
The HS code shown for Argon-39 is indicative (it is known at chapter level only). Confirm the classification with your customs broker before shipping.
Frequently asked questions
Quick answers about Argon-39, based on the data on this page
What is Argon-39?
What is the CAS number of Argon-39?
What is the molecular formula and weight of Argon-39?
What is Argon-39 used for?
Is Argon-39 hazardous?
What is the HS code of Argon-39?
Where can I buy Argon-39?
What is the price of Argon-39?
Guides for buyers
Practical guides that help when you source, ship or handle Argon-39
- Article, SourcingHow to write an RFQ that gets fast and accurate quotesWhat suppliers need to quote quickly and comparably: exact product identity, quantity and packing, delivery terms, documents, samples and payment, with a ready to use template.Read
- Guide, Trade and logisticsShipping dangerous goods: UN numbers, classes and packing groupsHow the UN dangerous goods system works for chemicals, from the nine classes and UN numbers to packing groups, UN packaging marks, labels, documents and segregation.Read
- Guide, Trade and logisticsHS codes for chemicals and why they matterHow the Harmonized System classifies chemicals, the chapters that matter, the rules for chemically defined compounds and mixtures, and practical steps to find the right code.Read
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