nobelium
Let an agent explain nobelium at public reference level, relay discovery history, naming dispute, isotopes and chemistry from IUPAC and nuclear science sources with attribution, describe the named isotopes, and distinguish nobelium from other actinides, transactinides and the Nobel Prize.
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 nobelium at public reference level, relay discovery history, naming dispute, isotopes and chemistry from IUPAC and nuclear science sources with attribution, describe the named isotopes, and distinguish nobelium from other actinides, transactinides and the Nobel Prize.
A synthetic radioactive actinide element with symbol No and atomic number 102, whose discovery claims from Stockholm in 1957, Berkeley in 1958 and Dubna in the 1960s were long disputed, with the IUPAC-IUPAP Transfermium Working Group in 1992 crediting the Dubna work, while the name nobelium, after Alfred Nobel, was retained; its known isotopes, including nobelium-250 to nobelium-255 and heavier ones, are short-lived, with nobelium-259 among the longest-lived at about an hour, so it is studied only atom by atom. The model stays at public reference level.
What it is for: Scientific research only.
It can be explain properties at reference level; relay discovery disputes with attribution; describe isotopes; distinguish related elements.
Distinguishing features
Synthetic
Disputed discovery
Short-lived
Divalent chemistry
What it looks like
Never seen in bulk; produced a few atoms at a time.
Physical character
atomic number: 102 number
longest-lived isotope: nobelium-259, about 58 minutes note
Transfermium Working Group report: 1992 year
stable oxidation state in water: +2 note - unusual for actinides
How it is recognised
Element 102, actinide
Nobelium-250, 251, 252, 253, 254 and 255 among other isotopes
Mendelevium is 101; lawrencium is 103; transactinides start at 104; the Nobel Prize is a separate namesake
Related models
is a kind of - in registry terms
is named after -
was credited by - with IUPAP in 1992 to Dubna
is contrasted with -
In practice
Families and kinds
light nobelium isotopes such as 250 to 255
heavier isotopes such as 259
nobelium ions in chemistry experiments
Identifiers
symbol No
CAS 10028-14-5
Standards and regulation
IUPAC element naming procedures
Radiation protection in accelerator laboratories
Failure modes and hazards
Presenting disputed discovery claims as settled
Overstating practical uses
Requests beyond public reference level, which are out of scope
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.nobelium
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 nobelium is.
Science.
Definition
Definition.
Definition
Definition.
- What is nobelium, and how does it differ from mendelevium, lawrencium, transactinides and the Nobel Prize? definition
- Is the question about chemistry, history or the naming dispute? boundary
Isotopes
Isotopes.
Isotopes
Isotopes.
- What are nobelium-250 to 255 and the longest-lived isotopes? definition
- Which entry fits the specific isotope? action
History Discovery.
Attribution.
Claims
Discovery claims.
Claims
Claims.
- What did the Stockholm, Berkeley and Dubna teams claim, and how did the 1992 report assess them? provenance
- Which references are standard? provenance
Naming
Naming.
Naming
Naming.
- Why was the name nobelium retained despite the credit to Dubna? provenance
- Which sources are cited? provenance
Science Chemistry and physics.
Science.
Chemistry
Chemistry.
Chemistry
Chemistry.
- Why is nobelium unusually stable in the +2 state? provenance
- Which entry fits actinide chemistry? action
Production
Production.
Production
Production.
- How is nobelium produced in accelerators, at reference level? provenance
- Which entry fits Joint Institute for Nuclear Research? action
Context Wider context.
Context.
Transfermium wars
Transfermium Wars.
Transfermium wars
Transfermium wars.
- What were the Transfermium Wars over element names? provenance
- Which entry fits Transfermium Wars? action
Stability
Nuclear structure.
Stability
Stability.
- What do nobelium isotopes reveal about nuclear shell structure? provenance
- Which entry fits island of stability? action
What the second pass must settle
- Should isotopes be separate entries?
- How should IUPAC sources be linked?
- How should the discovery dispute be presented?