Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Thiocyanic Acid

Thiocyanic Acid: colourless liquid.

CAS 463-56-9 CHNS 59.09 g/mol Warning

01 · Identification

What Thiocyanic Acid is

Thiocyanic Acid: colourless liquid. Its molecular formula is CHNS and its molecular weight is 59.09 g/mol. It melts at 5 °C.

Under the GHS it carries the signal word Warning.

02 · Identifiers

Thiocyanic Acid identifiers and molecular data

Thiocyanic Acid CAS number and EC number

CAS number463-56-9
EC number207-337-4
Index number (CLP Annex VI)615-003-00-8

Thiocyanic Acid molecular formula and molecular weight

Molecular formulaCHNS
Molecular weight59.09 g/mol

03 · GHS classification

Thiocyanic Acid hazard classification

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Thiocyanic Acid pictograms and signal word

Signal wordWarning

Thiocyanic Acid hazard class and category

GHS hazard classes Thiocyanic Acid falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Acute toxicity - dermal GHS chapter 3.1 Category 4 H312 GHS07
Acute toxicity - inhalation GHS chapter 3.1 Category 4 H332 GHS07
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 3 H412

Thiocyanic Acid hazard statements (H-codes)

Hazard statements assigned to Thiocyanic Acid
CodeHazard statement
H332 Harmful if inhaled.
H312 Harmful in contact with skin.
H302 Harmful if swallowed.
H412 Harmful to aquatic life with long lasting effects.

Thiocyanic Acid supplemental EU statements (EUH)

EU-specific statements assigned to Thiocyanic Acid. They exist only in CLP and have no counterpart in UN GHS.
CodeStatement
EUH032 Contact with acids liberates very toxic gas.

This page lists only the codes assigned to Thiocyanic Acid. 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 Thiocyanic Acid

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 Thiocyanic Acid 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

Thiocyanic Acid precautionary statements

CLP Annex VI assigns 12 precautionary statements to Thiocyanic Acid. 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.

Disposal

What has to happen to the contents and the empty container.

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

Thiocyanic Acid 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 тиоцианова киселина
Spanish español Ácido tiociánico
Czech čeština thiokyanatá kyselina
Danish dansk thiocyansyre
German Deutsch Thiocyansäure Rhodanwasserstoffsäure
Estonian eesti tiotsüaanhape
Greek ελληνικά θειοκυανικό οξύ
English English thiocyanic acid
French français acide thiocyanique
Croatian hrvatski tiocijanska kiselina
Italian italiano acido tiocianico
Latvian latviešu tiociānskābe
Lithuanian lietuvių tiocianato rūgštis
Hungarian magyar tiociánsav
Maltese Malti aċidu tijoċjaniku
Dutch Nederlands thiocyaanzuur
Polish polski kwas tiocyjanowy kwas rodanowodorowy
Portuguese português ácido tiociânico
Romanian română acid tiocianic
Slovak slovenčina kyselina tiokyanatá
Slovenian slovenščina tiocianska kislina
Finnish suomi tiosyaanihappo
Swedish svenska tiocyansyra

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

Thiocyanic Acid GHS label elements

Everything CLP Annex VI fixes for Thiocyanic Acid, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogram

Warning

Thiocyanic Acid

  • Harmful if inhaled.
  • Harmful in contact with skin.
  • Harmful if swallowed.
  • Harmful to aquatic life with long lasting effects.
  • Contact with acids liberates very toxic gas.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Do not eat, drink or smoke when using this product.
  • Use only outdoors or in a well-ventilated area.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF INHALED:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.
  • Wash with plenty of water/
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Thiocyanic Acid in the GHS label constructor →

07 · Health hazards

Thiocyanic Acid health hazards and exposure limits

Thiocyanic Acid hazard summary

A very strong acid; [Merck Index] Polymerizes on warming; Chronic exposure may cause hypothyroidism; [ICSC] See Sodium thiocyanate.

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

08 · Physical and chemical properties

Thiocyanic Acid 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.

Thiocyanic Acid melting point

Property Value Conditions Source
Melting point 5 °C (41 °F) ICSC

Thiocyanic Acid solubility

Property Value Conditions Source
Solubility Solubility in water: good ICSC

Thiocyanic Acid vapor pressure

Property Value Conditions Source
Vapor pressure 4.73 mmHg Haz-Map

Thiocyanic Acid vapor density

Property Value Conditions Source
Vapor density 2 (air = 1) ICSC

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

09 · Handling and storage

Thiocyanic Acid storage and handling

Thiocyanic Acid safe storage

Separated from strong oxidants, strong bases and food and feedstuffs. Ventilation along the floor.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

Planning storage for a mix of chemicals? Check Thiocyanic Acid in the storage compatibility matrix →

10 · Questions

Thiocyanic Acid — frequently asked questions

What is the CAS number of Thiocyanic Acid?

The CAS number of Thiocyanic Acid is 463-56-9. Its EC number is 207-337-4.

What is the chemical formula of Thiocyanic Acid?

The molecular formula of Thiocyanic Acid is CHNS and its molecular weight is 59.09 g/mol.

What does a Thiocyanic Acid label have to show?

Under CLP Annex VI the label for Thiocyanic Acid carries the pictogram Exclamation mark and the signal word is Warning.

Is Thiocyanic Acid flammable?

CLP Annex VI assigns Thiocyanic Acid 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 Thiocyanic Acid a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Thiocyanic Acid. 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 melting point of Thiocyanic Acid?

The melting point reported for Thiocyanic Acid is 5 °C (41 °F) (ICSC).

Nearby

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