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

p-toluenesulphonic acid (containing a maximum of 5 % H2SO4)

p-toluenesulphonic acid (containing a maximum of 5 % H2SO4) is monoclinic leaflets or prisms.

CAS 104-15-4 Warning

01 · Identification

What p-toluenesulphonic acid… is

p-toluenesulphonic acid (containing a maximum of 5 % H2SO4) is monoclinic leaflets or prisms. It boils at 38 °C, melts at 38 °C.

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

CAS number104-15-4
EC number203-180-0
Index number016-030-00-2
Chemical class Corrosives

Other names for p-toluenesulphonic acid…

  • p-toluenesulphonic acid (containing a maximum of 5 % H2SO4)

02 · GHS classification

Hazards and label elements

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

Signal wordWarning
Hazard statements assigned to p-toluenesulphonic acid…
CodeHazard statement
H335 May cause respiratory irritation.
H315 Causes skin irritation.
H319 Causes serious eye irritation.

Precautionary statements: P264, P280, P302, P305, P313, P332, P337, P338, P352

03 · Physical and chemical properties

p-toluenesulphonic 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.

Property Value Conditions Source
Boiling point 38 °C (100.4 °F) HSDB
140 °C (284 °F) at 20 mmHg (reduced pressure) HSDB
Melting point 38 °C (100.4 °F) METASTABLE FORM HSDB
106 °C (222.8 °F) monohydrate HSDB
105 °C (221 °F) CAMEO
Density 1.24 g/cm³ ICSC
1.45 g/cm³ at 25 °C CAMEO
Solubility ABOUT 67 G/100 ML WATER; SOL IN ALCOHOL, ETHER HSDB
VERY SOL IN WATER SODIUM SALT HSDB
Solubility in water, g/100ml at 25 °C: 67 (freely soluble) at 25 °C ICSC
Vapor pressure 0.0000027 mmHg Haz-Map
Flash point 183.89 °C (363 °F) HSDB
184 °C (363.2 °F) ICSC

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

04 · Handling and storage

Storing and handling p-toluenesulphonic acid…

Incompatible materials

Reacts with water.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check p-toluenesulphonic acid… in the storage compatibility matrix →

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