CompoundList
Sign in
Silicates, borates and other salts

Nitrogen trioxide

Also known as Dinitrogen trioxide, N-oxonitramide, Nitrogen oxide (N2O3)

CAS 10544-73-7Formula N2O3Molar mass 76.01 g/molEC 234-128-5
GHS signal word: Danger. Pictograms: Oxidiser, Gas under pressure, Corrosive, Acute toxicity (severe)
Get quotes Safety data
Nitrogen trioxide chemical structure, N2O3, CAS 10544-73-7
2D chemical structure

Key facts

What buyers check first

All properties
Physical form
Liquid
Melting point
-101.1 °C
Density
1.4 @ 2 °C
HS code
285390
Category
Silicates, borates and other salts
UN number
UN 2421
Illustrative photo, 200 litre blue HDPE drums of liquid in a warehouse
Typical packagingIllustrative packaging image, not the actual product

What is Nitrogen trioxide?

Plain description, key identifiers and synonyms

Dinitrogen trioxide is a nitrogen oxide.

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
N-oxonitramide
CAS number
10544-73-7 CAS number cross-checked
EC number
234-128-5
Molecular formula
N2O3
UNII
16E0524PXI
InChIKey
LZDSILRDTDCIQT-UHFFFAOYSA-N
InChI
InChI=1S/N2O3/c3-1-2(4)5
SMILES (canonical and isomeric)
N(=O)[N+](=O)[O-]

Synonyms

  • Dinitrogen trioxide
  • N-oxonitramide
  • Nitrogen oxide (N2O3)
  • Nitrous anhydride
  • Nitrogen trioxide 10% by volume or more
  • Dinitrogen trioxide (gas) (unlabeled N2O3)
  • Nitrogen trioxide [UN2421] [Poison gas]
  • trioxido-1kappa(2)O,2kappaO-dinitrogen(N--N)

Physical and chemical properties

Measured values and descriptors computed from the structure

Physical and chemical properties

Measured values, check the supplier specification for your grade

Physical form
Liquidexp.
Melting point
-101.1 °Cexp.
Density
1.4 @ 2 °Cexp.

Values vary by grade. Ask suppliers for the COA or TDS of the batch you buy.

Computed descriptors

Calculated from the structure, useful for screening and formulation

Molecular weight
76.01 g/molcalc.
Exact mass
75.9909 Dacalc.
LogP (octanol/water)
-0.06calc.
Topological polar surface area
72.57 Ųcalc.
Hydrogen bond donors
0calc.
Hydrogen bond acceptors
3calc.
Rotatable bonds
1calc.
Heavy atoms
5calc.
Rings
0calc.
Aromatic rings
0calc.
Fraction sp3 carbons
0calc.
Formal charge
0calc.
Stereocentres
0calc.

Calculated for screening. Confirm critical figures with the supplier.

Safety and hazards

GHS classification summary, not a safety data sheet

GHS signal word
Danger
GHS03: Oxidiser
Oxidiser
GHS04: Gas under pressure
Gas under pressure
GHS05: Corrosive
Corrosive
GHS06: Acute toxicity (severe)
Acute toxicity (severe)

Hazard statements

  • H270May cause or intensify fire, oxidiser.
  • H280Contains gas under pressure, may explode if heated.
  • H310 + H330Fatal in contact with skin. Fatal if inhaled.
  • H310Fatal in contact with skin.
  • H314Causes severe skin burns and eye damage.
  • H330Fatal if inhaled.
Precautionary statements (25)
  • P220Keep away from clothing and other combustible materials.
  • P244Keep valves and fittings free from oil and grease.
  • P260Do not breathe dust, fume, gas, mist, vapours or spray.
  • P262Do not get in eyes, on skin, or on clothing.
  • P264Wash skin thoroughly after handling.
  • P270Do not eat, drink or smoke when using this product.
  • P271Use only outdoors or in a well-ventilated area.
  • P280Wear protective gloves, protective clothing, eye protection and face protection.
  • P284In case of inadequate ventilation wear respiratory protection.
  • P301 + P330 + P331If swallowed: Rinse mouth. Do not induce vomiting.
  • P302 + P352If on skin: Wash with plenty of water.
  • P302 + P361 + P354If on skin: Take off immediately all contaminated clothing. Immediately rinse with water for several minutes.
  • P304 + P340If inhaled: Remove person to fresh air and keep comfortable for breathing.
  • P305 + P354 + P338If in eyes: Immediately rinse with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
  • P316Get emergency medical help immediately.
  • P320Specific treatment is urgent (see supplemental first aid instructions on the label).
  • P321Specific treatment (see supplemental first aid instructions on the label).
  • P361 + P364Take off immediately all contaminated clothing. And wash it before reuse.
  • P363Wash contaminated clothing before reuse.
  • P370 + P376In case of fire: Stop leak if safe to do so.
  • P403Store in a well-ventilated place.
  • P403 + P233Store in a well-ventilated place. Keep container tightly closed.
  • P405Store locked up.
  • P410 + P403Protect from sunlight. Store in a well-ventilated place.
  • P501Dispose of contents and container in accordance with local regulations.
UN number
UN 2421
Transport hazard class
2.3

GHS classification summary, not a safety data sheet (SDS). Classifications can differ by supplier, grade and concentration. Always check the supplier's SDS.

Full safety data and first aid

Nitrogen trioxide suppliers

Sponsored listings first, then the documented ranking: membership, verification, replies, completeness, freshness and ratings

No supplier listings yet

Post one free request and suppliers who make or trade Nitrogen trioxide can send you quotes. Your contact details stay private until you accept a quote.

Request quotesSell this chemical

Nitrogen trioxide price

Indicative price range per kg from live supplier offers

No published prices right now

Suppliers quote this chemical on request. Send one free request and compare quotes side by side.

Get latest price

Uses and applications

What the substance is used for, by industry and function

Applications are not documented for this substance yet. Suppliers often describe uses on their product pages, linked in the suppliers list above.

Regulatory status

Inventories, regulations and trade controls that list this substance

United States

  • TSCA inventory (USA)
    Status: Active in US commerce

HS code and trade data

Customs classification and reported world trade statistics

Global trade

World import and export statistics for the HS code Nitrogen trioxide is traded under.

HS 2853.90Indicative HS code

Phosphides, whether or not chemically defined, excluding ferrophosphorus, other, other

World exports in 2024
$2.45B
−33.6% vs 2023, imports $816M
2019 to 2024
Top exporters
  1. China68.4%
  2. Israel8.1%
  3. United States4.9%
Top importers
  1. United States19.3%
  2. Japan17.9%
  3. China13.4%
Reported customs values in USD, not prices.Full trade data

The HS code shown for Nitrogen trioxide is indicative (it is known at chapter level only). Confirm the classification with your customs broker before shipping.

Frequently asked questions

Quick answers about Nitrogen trioxide, based on the data on this page

What is Nitrogen trioxide?

Dinitrogen trioxide is a nitrogen oxide.

What is the CAS number of Nitrogen trioxide?

The CAS registry number of Nitrogen trioxide is 10544-73-7.

What is the molecular formula and weight of Nitrogen trioxide?

The molecular formula of Nitrogen trioxide is N2O3 and its molar mass is 76.01 g/mol.

Is Nitrogen trioxide hazardous?

Nitrogen trioxide carries the GHS signal word "Danger". Main hazards: may cause or intensify fire, oxidiser, contains gas under pressure, may explode if heated, fatal in contact with skin. fatal if inhaled. This summary is not an SDS, always read the supplier safety data sheet.

What is the HS code of Nitrogen trioxide?

Nitrogen trioxide is usually classified under HS code 285390 (Phosphides, whether or not chemically defined, excluding ferrophosphorus, other…). This is indicative, confirm it with your customs broker before shipping.

Where can I buy Nitrogen trioxide?

Post a free request on CompoundList and suppliers of Nitrogen trioxide will send you quotes. Your contact details stay private until you accept a quote.

What is the price of Nitrogen trioxide?

Suppliers quote Nitrogen trioxide on request because prices depend on grade, purity, quantity and destination. A free request on CompoundList gets you several quotes to compare.

Guides for buyers

Practical guides that help when you source, ship or handle Nitrogen trioxide

Get quotes for Nitrogen trioxide

Post one free request with your grade, quantity and destination. Matching suppliers send quotes you can compare side by side.
Post a request Sell Nitrogen trioxide
Data last updated 7 Oct 2026. Details may have changed, please confirm them with the supplier. Report an error on this page
Embed this structure on your websiteShow code

Paste this code into your page to show the 2D structure of Nitrogen trioxide with a 3D view, its CAS number where known and a link back to this page. Free to use with the link kept.

<iframe src="https://www.compoundlist.com/embed/structure/nitrogen-trioxide-10544-73-7" title="Nitrogen trioxide structure on CompoundList" width="360" height="420" style="border:1px solid #E7E2DA;border-radius:12px;max-width:100%" loading="lazy" referrerpolicy="strict-origin-when-cross-origin"></iframe>
Preview the embed

Explore more in Silicates, borates and other salts or HS code 285390

Price on request
Free quotes, contact stays private
Get quotes