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

Potassium hydrogensulphate

Potassium hydrogensulphate: large Crystals; Other Solid; Dry Powder; Large Crystals.

CAS 7646-93-7 HKO4S 136.17 g/mol Danger

01 · Identification

What Potassium hydrogensulphate is

Potassium hydrogensulphate: large Crystals; Other Solid; Dry Powder; Large Crystals. Its molecular formula is HKO4S and its molecular weight is 136.17 g/mol.

Under the GHS it carries the signal word Danger. It is classed as corrosives.

02 · Identifiers

Potassium hydrogensulphate identifiers and molecular data

Potassium hydrogensulphate CAS number and EC number

CAS number7646-93-7
EC number231-594-1
Index number (CLP Annex VI)016-056-00-4

Potassium hydrogensulphate molecular formula and molecular weight

Molecular formulaHKO4S
Molecular weight136.17 g/mol
Chemical class Corrosives

03 · GHS classification

Potassium hydrogensulphate hazard classification

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

Potassium hydrogensulphate pictograms and signal word

Signal wordDanger

Potassium hydrogensulphate hazard class and category

GHS hazard classes Potassium hydrogensulphate falls into
Hazard class Category From code Pictogram
Skin corrosion/irritation GHS chapter 3.2 Category 1A or 1B or 1C H314 GHS05
Specific target organ toxicity - single exposure GHS chapter 3.8 Category 3 H335 GHS07

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 hydrogensulphate hazard statements (H-codes)

Hazard statements assigned to Potassium hydrogensulphate
CodeHazard statement
H335 May cause respiratory irritation.
H314 Causes severe skin burns and eye damage.

This page lists only the codes assigned to Potassium hydrogensulphate. 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 hydrogensulphate

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 hydrogensulp… 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 hydrogensulphate precautionary statements

CLP Annex VI assigns 5 precautionary statements to Potassium hydrogensulphate. 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.

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 hydrogensulphate 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 хидрогенсулфат
Spanish español Hidrogenosulfato de potasio
Czech čeština hydrogensíran draselný
Danish dansk kaliumhydrogensulfat
German Deutsch Kaliumhydrogensulfat
Estonian eesti kaaliumvesiniksulfaat
Greek ελληνικά όξινο θειικό κάλιο
English English potassium hydrogensulphate
French français hydrogénosulfate de potassium
Croatian hrvatski kalijev hidrogensulfat
Italian italiano idrogenosolfato di potassio
Latvian latviešu kālija hidrogēnsulfāts
Lithuanian lietuvių kalio vandenilio sulfatas
Hungarian magyar kálium-hidrogén-szulfát
Maltese Malti idroġensulfat tal-potassju
Dutch Nederlands kaliumwaterstofsulfaat
Polish polski wodorosiarczan(VI) potasu kwaśny siarczan potasu
Portuguese português hidrogenossulfato de potássio
Romanian română hidrogenosulfat de potasiu
Slovak slovenčina hydrogensíran draselný
Slovenian slovenščina kalijev hidrogensulfat
Finnish suomi kaliumvetysulfaatti
Swedish svenska kaliumvätesulfat

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 hydrogensulphate GHS label elements

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

GHS05 Corrosion pictogramGHS07 Exclamation mark pictogram

Danger

Potassium hydrogensulphate

  • May cause respiratory irritation.
  • Causes severe skin burns and eye damage.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • Immediately call a POISON CENTER/doctor/
  • Do NOT induce vomiting.

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

Need this as an actual label? Open Potassium hydrogensulphate in the GHS label constructor →

07 · Health hazards

Potassium hydrogensulphate health hazards and exposure limits

Potassium hydrogensulphate hazard summary

Reacts with water; A corrosive substance that can cause injury to the skin, eyes, and respiratory tract; [ICSC] Causes burns; May cause respiratory irritation; [Aldrich MSDS]

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

08 · Physical and chemical properties

Potassium hydrogensulphate 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 hydrogensulphate density

Property Value Conditions Source
Density 2.2 g/cm³ ICSC
2.24 g/cm³ at 25 °C DOE PAC

Potassium hydrogensulphate solubility

Property Value Conditions Source
Solubility Solubility in water, g/100ml: 49 (very good) ICSC
Freely soluble in water, insoluble in ethanol EU Food Improvement Agents

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

09 · Handling and storage

Potassium hydrogensulphate storage and handling

Potassium hydrogensulphate safe storage

Dry. Separated from strong bases, alcohols, metals and food and feedstuffs.

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

Potassium hydrogensulphate reactivity

Acidic salts, such as POTASSIUM HYDROGEN SULFATE, are generally soluble in water. The resulting solutions contain moderate concentrations of hydrogen ions and have pH's of less than 7.0. They react as acids to neutralize bases. These neutralizations generate heat, but less or far less than is generated by neutralization of inorganic acids, inorganic oxoacids, and carboxylic acid. They usually do not react as either oxidizing agents or reducing agents but such behavior is not impossible. Many of these compounds catalyze organic reactions.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Potassium hydrogensulphat… in the storage compatibility matrix →

10 · Questions

Potassium hydrogensulphate — frequently asked questions

What is the CAS number of Potassium hydrogensulphate?

The CAS number of Potassium hydrogensulphate is 7646-93-7. Its EC number is 231-594-1.

What is the chemical formula of Potassium hydrogensulphate?

The molecular formula of Potassium hydrogensulphate is HKO4S and its molecular weight is 136.17 g/mol.

What does a Potassium hydrogensulphate label have to show?

Under CLP Annex VI the label for Potassium hydrogensulphate carries the pictograms Corrosion and Exclamation mark and the signal word is Danger.

Is Potassium hydrogensulphate flammable?

CLP Annex VI assigns Potassium hydrogensulphate 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 hydrogensulphate a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Potassium hydrogensulphate. 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.

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