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Research draft

scandium

vr.tr.scandium · PHY.MAT

Let an agent identify scandium and its properties, relay occurrence, production, uses and supply issues from reference sources, and distinguish it from other rare earths and from yttrium.

Thing Registry Physical world and living systems

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 identify scandium and its properties, relay occurrence, production, uses and supply issues from reference sources, and distinguish it from other rare earths and from yttrium.

A chemical element with symbol Sc and atomic number 21, a soft silvery transition metal classified with the rare earth elements, occurring in trace amounts in many minerals and recovered mainly as a by-product of uranium, titanium and aluminium processing, used in small amounts in aluminium-scandium alloys for aerospace and sports equipment, in solid oxide fuel cells and in high-intensity lamps; scandium has one stable isotope, scandium-45, with radioactive isotopes from scandium-36 upward, and its supply is small and expensive.

What it is for: Alloys, fuel cells and lighting.

It can be relay properties and isotopes; explain occurrence and production; relay uses and supply; distinguish from related elements.

Distinguishing features

Light rare earth

Single stable isotope

By-product production

Small costly supply

What it looks like

A silvery white metal that develops a yellowish or pinkish cast in air.

Physical character

atomic number: 21 Z

standard atomic weight: 44.956 u

density: 2.985 g/cm3

melting point: 1541 degrees C

How it is recognised

Element 21, symbol Sc

Light rare earth metal of aluminium alloys

Yttrium is the heavier group member; titanium is the neighbouring element

Related models

is a kind of - in registry terms

rare earth element

is a kind of - in registry terms

light metal

is used in - the main metal use

aluminium-scandium alloy

is adjacent to - element 22

titanium

In practice

Families and kinds

scandium metal

scandium compounds such as the oxide and fluoride

scandium-45 as the stable isotope and radioactive isotopes such as scandium-46

aluminium-scandium alloys

scandium in fuel cells and lamps

Identifiers

symbol Sc

CAS 7440-20-2

Standards and regulation

Critical raw material listings

Chemical safety data sheets

Aerospace material specifications for alloys

Failure modes and hazards

Supply scarcity and price

Confusing with yttrium and lanthanides

Radioactive isotope handling in research

Also called

scandium-36scandium-37scandium-38scandium-39scandium-40scandium-41scandium-42scandium-43scandium-44scandium-48scandium-49scandium-50scandium-51scandium-52scandium-53scandium-54scandium-55scandium-56scandium-57scandium-58scandium-59scandium-60scandium-38mscandium-42mscandium-43m1scandium-43m2scandium-44m1scandium-44m2scandium-44m3scandium-45mscandium-46m1scandium-46m2scandium-47mscandium-50mscandium-54mscandium-46scandium-45scandium-47scandium-61

Where this came from

wikidata · CC0 1.0

Also registered as vr.tr.scandium

Drafted structure

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

Identify What scandium is.

Identity.

Properties

Properties.

Properties

Properties.

  1. What are the physical and chemical properties of scandium? definition
  2. Is the question about scandium or a neighbouring element? boundary

Isotopes

Isotopes.

Isotopes

Isotopes.

  1. Which isotopes exist, and how are radioactive ones used? definition
  2. Which entry fits the specific isotope? action
Source Occurrence and production.

Supply.

Occurrence

Occurrence.

Occurrence

Occurrence.

  1. Where does scandium occur, and how is it recovered as a by-product? provenance
  2. Which entry fits thortveitite? action

Supply

Supply.

Supply

Supply.

  1. Who produces scandium, and why is supply small and costly, with sources? measurement
  2. Which sources are cited? provenance
Use Uses.

Application.

Alloys

Alloys.

Alloys

Alloys.

  1. How does scandium strengthen aluminium alloys, and where are they used? provenance
  2. Which references are standard? provenance

Other

Fuel cells and lamps.

Other

Other.

  1. How is scandium used in solid oxide fuel cells and metal halide lamps? provenance
  2. Which entry fits solid oxide fuel cell? action
Context History and outlook.

Context.

Discovery

Discovery.

Discovery

Discovery.

  1. How was scandium predicted by Mendeleev and discovered by Nilson in 1879? provenance
  2. Which entry fits the history of the periodic table? action

Outlook

Supply outlook.

Outlook

Outlook.

  1. What new sources and projects are reported for scandium supply? provenance
  2. Is the presentation attributed? boundary

What the second pass must settle

  • Should aluminium-scandium alloy be a separate entry?
  • How should supply data be linked?
  • The registry entry has merged aliases naming short-lived isotopes; should they be split off?