Substance profile
Potassium Chlorate
Potassium Chlorate is colorless, lustrous crystals or white granules or powder.
01 · Identification
What Potassium Chlorate is
Potassium Chlorate is colorless, lustrous crystals or white granules or powder. It boils at 400 °C, melts at 368 °C.
Under the GHS it carries the signal word Danger. It is classed as reactive agents - 1st degree.
02 · Identifiers
Potassium Chlorate identifiers and molecular data
Potassium Chlorate CAS number and EC number
Potassium Chlorate molecular formula and molecular weight
03 · GHS classification
Potassium Chlorate hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Potassium Chlorate pictograms and signal word
Potassium Chlorate hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Oxidising liquids or Oxidising solids | Category 1 | H271 | GHS03 |
| Acute toxicity - oral GHS chapter 3.1 | Category 3 | H301 | GHS06 |
Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.
Potassium Chlorate hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H271 | May cause fire or explosion; strong oxidiser. |
| H301 | Toxic if swallowed. |
This page lists only the codes assigned to Potassium Chlorate. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.
Safety Data Sheet
Getting an SDS for Potassium Chlorate
A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Potassium Chlorate issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.
04 · Precautionary statements
Potassium Chlorate precautionary statements
CLP Annex VI assigns 4 precautionary statements to Potassium Chlorate. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.
Prevention
What to do before and during handling so the hazard never happens.
Response
What to do once exposure, spillage or fire has already happened.
Reading the notation. … is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.
05 · Names in the regulation
Potassium Chlorate name in 23 EU languages
CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.
| Language | Name in CLP Annex VI Part 3 |
|---|---|
| Bulgarian български | калиев хлорат |
| Spanish español | Clorato de potasio |
| Czech čeština | chlorečnan draselný |
| Danish dansk | kaliumchlorat |
| German Deutsch | Kaliumchlorat |
| Estonian eesti | kaaliumkloraat |
| Greek ελληνικά | χλωρικό κάλιο |
| English English | potassium chlorate |
| French français | chlorate de potassium |
| Croatian hrvatski | kalijev klorat |
| Italian italiano | clorato di potassio |
| Latvian latviešu | kālija hlorāts |
| Lithuanian lietuvių | kalio chloratas |
| Hungarian magyar | kálium-klorát |
| Maltese Malti | klorat tal-potassju |
| Dutch Nederlands | kaliumchloraat |
| Polish polski | chloran(V) potasu |
| Portuguese português | clorato de potássio |
| Romanian română | clorat de potasiu |
| Slovak slovenčina | chlorečnan draselný |
| Slovenian slovenščina | kalijev klorat |
| Finnish suomi | kaliumkloraatti |
| Swedish svenska | kaliumklorat |
All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.
06 · Label elements
Potassium Chlorate GHS label elements
Everything CLP Annex VI fixes for Potassium Chlorate, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Potassium Chlorate
- May cause fire or explosion; strong oxidiser.
- Toxic if swallowed.
- Do not eat, drink or smoke when using this product.
- IF SWALLOWED:
- Immediately call a POISON CENTER/doctor/…
- Rinse mouth.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Potassium Chlorate in the GHS label constructor →
07 · Health hazards
Potassium Chlorate health hazards and exposure limits
Potassium Chlorate hazard summary
A skin and eye irritant; toxic by ingestion; [CAMEO] Irritating to the G.I. tract and can cause blood hemolysis and methemoglobinemia; [Merck Index] A respiratory tract irritant; [ICSC] Very toxic after ingestion with a lethal dose of about 50-500 mg/kg; Methemoglobinemia, hemolysis, and kidney injury have been reported after ingestion; [HSDB]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
08 · Physical and chemical properties
Potassium Chlorate properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
Potassium Chlorate boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 400 °C (752 °F) | decomposes, decomposes | HSDB |
Potassium Chlorate melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 368 °C (694.4 °F) | HSDB | |
| 360 °C (680 °F) | CAMEO |
Potassium Chlorate density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 2.32 g/cm³ | HSDB | |
| 2.3 g/cm³ | ICSC | ||
| 2.34 g/cm³ | at 20 °C | CAMEO |
Potassium Chlorate solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | 1 g dissolves slowly in 16.5 ml water, 1.8 ml boiling water, about 50 ml glycerol; almost insol in alcohol | HSDB | |
| SLIGHTLY SOL IN LIQUID AMMONIA; INSOL IN ACETONE; SOL IN ALKALIES | HSDB | ||
| 8.61 g/100 g water at 25 °C | at 25 °C | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Potassium Chlorate fire and explosion behaviour
These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.
Potassium Chlorate fire potential
Not flammable, but may cause fire upon contact with ordinary combustibles.
Source: Hazardous Substances Data Bank (HSDB)
Fire and explosion
EXPLODES WITH SULFURIC ACID; INFLAMES WITH EXPLOSION IF TRITURATED WITH ANY ORG SUBSTANCES, SULFUR, PHOSPHORUS, SULFITE, HYPOPHOSPHITE, & OTHER OXIDIZABLE SUBSTANCES.
Source: HSDB
Contact with oxidizable substances may cause extremely violent combustion. Explodes with sulfuric acid. Inflames with explosion if triturated with any organic substances, sulfur, phosphorus, sulfite, hypophosphite and other oxidizable substances. Sealed containers may rupture when heated. Sensitive to mechanical impact.
Source: HSDB
Forms sensitive explosive mixtures with agricultural materials, ... aluminum + antimony trisulfide powders, arsenic trisulfide, carbon, charcoal + potassium nitrate + sulfur, charcoal + sulfur, cyanides, cyanoguanidine, hydrocarbons, manganese dioxide + traces of organic matter, manganese dioxide + potassium hydroxide, metal + wood, metal phosphides, ... metal phosphinates, ... finely divided metals, ... metal phosphides, ... metal thiocyanates, ... nitric acid + organic materials, powdered nonmetals, ... reducing agents, ... sugars, ... sulfur, sulfur + metal derivatives, ... sulfuric acid, sodium amide, tannic acid.
Source: HSDB
10 · Handling and storage
Potassium Chlorate storage and handling
Potassium Chlorate safe storage
Separated from combustible substances, reducing agents, strong acids, organic chemicals, ammonium compounds, powdered metals and food and feedstuffs. Dry.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Potassium Chlorate storage conditions
... Containers of potassium chlorate should be protected from physical damage and sudden shocks.
Source: Hazardous Substances Data Bank (HSDB)
Potassium Chlorate incompatible materials
Violent reaction or ignition with ... ammonium salts, ammonium sulfate, Sb2S3, arsenic, barium hypophosphite, BaS, calcium hypophosphite, CaS, charcoal, Cu3P2, fabrices, ... lactose, (Mg + CuSO4 (anhydrous) + NH4NO3 + water), MnO2, dinickel trioxide, dibasic organic acids, organic matter, NaNH2, sugar + sulfuric acid, sucrose, SO2, sulfuric acid, thiocyanates, thorium dicarbide, sodium amide, KOH, metal hypophosphites.
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check Potassium Chlorate in the storage compatibility matrix →
11 · Transport
Potassium Chlorate UN number and transport classification
Transport classification is a separate system from the GHS classification above. It decides how a package is marked and how a load may be carried; it does not follow from the workplace label, and the workplace label does not follow from it. The entries below are linked by CAS number, never by name.
The same CAS number is shipped under more than one UN number. Which entry applies follows from the form and the concentration of the consignment — read the proper shipping name, not the CAS.
Potassium Chlorate under UN 1485 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| POTASSIUM CHLORATE | 5.1 | O2 | II | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 5.1 is “Oxidizing substances” (ADR 2.1.1.1).
United States · 49 CFR 172.101 Hazardous Materials Table
| Proper shipping name (column 2) | Class or division | PG | Labels (column 6) |
|---|---|---|---|
| Potassium chlorate | 5.1 | II | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 5.1 is “Oxidizer” (49 CFR 173.2).
Potassium Chlorate under UN 2427 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| POTASSIUM CHLORATE, AQUEOUS SOLUTION | 5.1 | O1 | II | |
| POTASSIUM CHLORATE, AQUEOUS SOLUTION | 5.1 | O1 | III | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 5.1 is “Oxidizing substances” (ADR 2.1.1.1).
United States · 49 CFR 172.101 Hazardous Materials Table
| Proper shipping name (column 2) | Class or division | PG | Labels (column 6) |
|---|---|---|---|
| Potassium chlorate, aqueous solution | 5.1 | II | |
| Potassium chlorate, aqueous solution | 5.1 | III | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 5.1 is “Oxidizer” (49 CFR 173.2).
12 · Questions
Potassium Chlorate — frequently asked questions
What is the CAS number of Potassium Chlorate?
The CAS number of Potassium Chlorate is 3811-04-9. Its EC number is 223-289-7.
What does a Potassium Chlorate label have to show?
Under CLP Annex VI the label for Potassium Chlorate carries the pictograms Flame over circle and Skull and crossbones and the signal word is Danger.
Is Potassium Chlorate flammable?
CLP Annex VI assigns Potassium Chlorate no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.
Is Potassium Chlorate a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Potassium Chlorate. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.
What is the boiling point of Potassium Chlorate?
The boiling point reported for Potassium Chlorate is 400 °C (752 °F), decomposes, decomposes (HSDB).
What is the melting point of Potassium Chlorate?
The melting point reported for Potassium Chlorate is 368 °C (694.4 °F) (HSDB).
How should Potassium Chlorate be stored?
... Containers of potassium chlorate should be protected from physical damage and sudden shocks. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Potassium Chlorate
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