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Research draft

nitrogen

vr.tr.nitrogen · PHY.MAT

Let an agent identify nitrogen and its properties, relay its atmospheric, biological and industrial roles, explain the nitrogen cycle and environmental issues with sources, and distinguish the element from its compounds and from soil and dissolved nitrogen pools.

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 nitrogen and its properties, relay its atmospheric, biological and industrial roles, explain the nitrogen cycle and environmental issues with sources, and distinguish the element from its compounds and from soil and dissolved nitrogen pools.

A chemical element with symbol N and atomic number 7, a colourless, odourless diatomic gas making up about 78 percent of the atmosphere, essential to life in proteins and nucleic acids, and cycled through soils, water and organisms in organic and inorganic forms; nitrogen is produced industrially by air separation, converted to ammonia for fertilisers, and its compounds are central to agriculture, explosives and pollution, with two stable isotopes, nitrogen-14 and nitrogen-15.

What it is for: Inert atmosphere, fertiliser production, cryogenics and chemical industry.

It can be relay properties and isotopes; explain the nitrogen cycle; relay industrial uses and safety; distinguish element from compounds and pools.

Distinguishing features

Triple-bonded diatomic gas

Atmospheric abundance

Biological essential

Fixed industrially by the Haber process

What it looks like

A colourless, odourless gas; a colourless liquid when cryogenically cooled.

Physical character

atomic number: 7 Z

standard atomic weight: 14.007 u

boiling point: -195.8 degrees C

share of atmosphere: about 78 percent - by volume

How it is recognised

Element 7, symbol N, diatomic gas

78 percent of air

Nitrates, ammonia and soil nitrogen are compounds or pools, not the element

Related models

is a kind of - in registry terms

diatomic nonmetal

is a kind of - group 15

pnictogen

is cycled by - through the biosphere

nitrogen cycle

is fixed by - into ammonia

Haber process

In practice

Families and kinds

nitrogen gas and liquid nitrogen

isotopes nitrogen-14 and nitrogen-15, with radioactive isotopes from nitrogen-10 to nitrogen-25

nitrogen pools: soil nitrogen, soil organic nitrogen, dissolved organic nitrogen

nitrogen compounds such as ammonia, nitrates and nitrogen oxides

allotropes and polymeric forms under extreme conditions

Identifiers

symbol N

CAS 7727-37-9

Standards and regulation

Cryogenic and compressed gas safety standards

Fertiliser and nitrate regulations such as the EU Nitrates Directive

Air quality rules on nitrogen oxides

Chemical safety data sheets

Failure modes and hazards

Asphyxiation in confined spaces

Cold burns from liquid nitrogen

Eutrophication and air pollution from nitrogen compounds

Confusing element with compounds

Also called

allotrope of nitrogendissolved organic nitrogensoil nitrogennitrogen-14soil organic nitrogennitrogen-22nitrogen-19nitrogen-20nitrogen-18nitrogen-17nitrogen-16nitrogen-25nitrogen-24nitrogen-23nitrogen-21nitrogen-10nitrogen-11nitrogen-12nitrogen-11massimilable nitrogennitrogen-13solid nitrogennitrogen-15urea nitrogenreactive nitrogentotal Kjeldahl nitrogenδ15N

Where this came from

wikidata · CC0 1.0

Also registered as vr.tr.nitrogen

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 nitrogen is.

Identity.

Properties

Properties.

Properties

Properties.

  1. What are the physical and chemical properties of nitrogen? definition
  2. Is the question about the element, a compound or an environmental nitrogen pool? boundary

Isotopes

Isotopes.

Isotopes

Isotopes.

  1. Which isotopes exist, and how is nitrogen-15 used as a tracer? definition
  2. Which entry fits the specific isotope? action
Cycle The nitrogen cycle.

Science.

Cycle

Cycle.

Cycle

Cycle.

  1. How does nitrogen move through fixation, nitrification, assimilation and denitrification? provenance
  2. Which entry fits nitrogen cycle? action

Pools

Soil and water pools.

Pools

Pools.

  1. What are soil nitrogen, soil organic nitrogen and dissolved organic nitrogen, and why do they matter? provenance
  2. Which references are standard? provenance
Industry Uses and safety.

Application.

Uses

Uses.

Uses

Uses.

  1. How is nitrogen produced and used, from fertilisers to cryogenics and inert atmospheres? provenance
  2. Which entry fits the Haber process? action

Safety

Safety.

Safety

Safety.

  1. What hazards do nitrogen gas and liquid present, and what rules apply? provenance
  2. Is the user asking about a confined space or exposure, which needs safety professionals? boundary
Environment Environment and history.

Context.

Pollution

Nitrogen pollution.

Pollution

Pollution.

  1. How do nitrogen compounds cause eutrophication and air pollution, and how are they regulated, with sources? provenance
  2. Which sources are cited? provenance

History

History.

History

History.

  1. How was nitrogen discovered, and how did the Haber-Bosch process change agriculture? provenance
  2. Which entry fits the history of chemistry? action

What the second pass must settle

  • Should the nitrogen cycle and nitrogen pollution be separate primary entries?
  • How should environmental data be linked?
  • The registry entry has merged aliases naming isotopes and environmental pools; should they be split off?