Substance profile
Benzoyl Peroxide
Benzoyl Peroxide is crystals with a faint, benzaldehyde-like odor.
01 · Identification
What Benzoyl Peroxide is
Benzoyl Peroxide is crystals with a faint, benzaldehyde-like odor. Its molecular formula is C14H10O4 and its molecular weight is 242.23 g/mol. It melts at 105 °C.
Under the GHS it carries the signal word Danger. It is classed as flammable agents - 4th degree.
Other names for Benzoyl Peroxide
- dibenzoyl peroxide
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.
| Code | Hazard statement |
|---|---|
| H241 | Heating may cause a fire or explosion. |
| H319 | Causes serious eye irritation. |
| H317 | May cause an allergic skin reaction. |
| H400 | Very toxic to aquatic life. |
| H410 | Very toxic to aquatic life with long lasting effects. |
Precautionary statements: P261, P264, P272, P273, P280, P305, P313, P333, P337, P338, P391, P501
03 · Physical and chemical properties
Benzoyl Peroxide 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 | Decomposes explosively | decomposes | NIOSH |
| Decomposes explosively (NTP, 1992) | decomposes | CAMEO | |
| decomposes explosively | decomposes | OSHA | |
| Melting point | 104.5 °C (220.1 °F) | HSDB | |
| 102.78 °C (217 °F) | NIOSH | ||
| Density | 1.33 g/cm³ | NIOSH | |
| 1.3 g/cm³ | ICSC | ||
| 1.334 g/cm³ | at 25 °C | HSDB | |
| Solubility | Sparingly soluble in water | HSDB | |
| Slightly soluble in water | HSDB | ||
| In water, 9.10 mg/L at 25 °C | at 25 °C | HSDB | |
| Vapor pressure | 1 mmHg | below this value | NIOSH |
| 0.1 mmHg | below this value, at 20 °C | HSDB | |
| Flash point | 80 °C (176 °F) | HSDB | |
| Autoignition temperature | 80 °C (176 °F) | HSDB | |
| Lower explosive limit (LEL) | May explode when heated. | HSDB | |
| Combustible Solid (easily ignited and burns very rapidly). | NIOSH |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Fire and explosion
Fire and explosion behaviour of Benzoyl Peroxide
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.
Fire and explosion
Benzoyl peroxide has been reported to explode for apparently no specific reason. Friction while opening bottles has caused other explosions. Purification of benzoyl peroxide in hot chloroform solutions has also resulted in several explosions. Purification in cold chloroform by addition of methanol is without danger.
Source: HSDB
05 · Handling and storage
Storing and handling Benzoyl Peroxide
Storage conditions
Keep container tightly closed in a dry and well-ventilated place. Storage class (TRGS 510): Other explosive hazardous materials.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
Incompatible materials: Alcohols, metals.
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check Benzoyl Peroxide in the storage compatibility matrix →