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Research draft

chlorine

vr.tr.chlorine · PHY.MAT

Let an agent describe chlorine and its properties, relay uses, production and biological roles from chemistry references, relay safety and regulation in general terms, and note its history as a weapon without operational detail.

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 describe chlorine and its properties, relay uses, production and biological roles from chemistry references, relay safety and regulation in general terms, and note its history as a weapon without operational detail.

A chemical element with symbol Cl and atomic number 17, a yellow-green diatomic gas and the second lightest halogen, highly reactive and toxic, with stable isotopes chlorine-35 and chlorine-37 and radioactive isotopes from chlorine-28 to chlorine-52 including the long-lived chlorine-36 used in dating, occurring mainly as chloride in seawater and salt deposits and produced by electrolysis of brine; chlorine is used for water disinfection, bleaching, PVC and many chemicals, is essential to life as chloride, and was used as a chemical weapon in the First World War.

What it is for: Disinfection, bleaching and chemical manufacture.

It can be describe properties and isotopes; relay uses and production; relay safety and regulation; note history.

Distinguishing features

Reactive halogen

Diatomic gas

Disinfectant use

Toxicity

What it looks like

A yellow-green gas with a sharp smell; chlorides are usually white solids.

Physical character

atomic number: 17 count

boiling point: -34 C

chlorine-36 half-life: about 301000 years

world production: about 80 million tonnes - per year

How it is recognised

Halogen element 17

Chlorine gas, chloride ion, isotopes Cl-35, Cl-37, Cl-36 and short-lived Cl-28 to Cl-43

Chloride is the ion; hypochlorite is bleach; chlorinated compounds are derivatives

Related models

is a kind of - in registry terms

halogens

is a kind of - in registry terms

diatomic nonmetal

forms - its common ion

chloride

is produced by - from brine

chloralkali process

In practice

Families and kinds

chlorine gas

chloride salts

hypochlorites and chlorine dioxide as disinfectants

organochlorine compounds including PVC

isotopes: stable Cl-35 and Cl-37, cosmogenic Cl-36, and short-lived isotopes such as Cl-28, Cl-39 to Cl-43

Identifiers

symbol Cl

CAS 7782-50-5

Standards and regulation

Chemical safety and transport rules for chlorine gas

Drinking water disinfection standards

Chemical Weapons Convention

Industrial emission and REACH regulations

Failure modes and hazards

Toxic gas release

Mixing bleach with acids or ammonia in homes

Agents providing operational detail on harmful uses

Disinfection by-products

Also called

chlorine-39chlorine-40chlorine-41chlorine-42chlorine-43chlorine-28chlorine-29chlorine-30chlorine-31chlorine-32chlorine-33chlorine-34chlorine-44chlorine-45chlorine-46chlorine-47chlorine-48chlorine-49chlorine-50chlorine-51chlorine-34mchlorine-38mchlorine-36chlorine-38chlorine-35chlorine-37

Where this came from

wikidata · CC0 1.0

Also registered as vr.tr.chlorine

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 chlorine is.

Science.

Properties

Properties.

Properties

Properties.

  1. What are the physical and chemical properties of chlorine, and why is it so reactive? definition
  2. Is the question about the element, chloride, bleach or a chlorinated compound? boundary

Isotopes

Isotopes.

Isotopes

Isotopes.

  1. What isotopes of chlorine exist, and how is chlorine-36 used in dating? definition
  2. Which entry fits the specific isotope? action
Use Uses and production.

Application.

Uses

Uses.

Uses

Uses.

  1. How is chlorine used in water treatment, bleaching, PVC and chemical manufacture? provenance
  2. Which references are standard? provenance

Production

Production.

Production

Production.

  1. How is chlorine produced by the chloralkali process, in general terms? provenance
  2. Which entry fits chloralkali process? action
Safety Safety and biology.

Regulation.

Safety

Safety.

Safety

Safety.

  1. What hazards does chlorine pose, and what safety rules and household precautions apply? provenance
  2. Is the user describing an exposure, which needs emergency services or poison control now? boundary

Biology

Biology.

Biology

Biology.

  1. What role does chloride play in the body and in the environment? provenance
  2. Which sources are cited? provenance
Context History.

Context.

Discovery

Discovery.

Discovery

Discovery.

  1. How was chlorine discovered by Scheele and identified as an element by Davy? provenance
  2. Which entry fits the history of chemistry? action

Weapon

Chemical weapon history.

Weapon

Weapon.

  1. How was chlorine used as a weapon in the First World War, and how is it regulated today, as historians and treaties describe? provenance
  2. Is the question seeking harmful operational detail the model does not provide? boundary

What the second pass must settle

  • Should chloride and chloralkali process be separate primary entries?
  • How should chemistry references be linked?
  • The registry entry has merged aliases naming many isotopes; should they be split off?