Acetaldehyde

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The main aldehyde it has in the wine. It is a distinctive and pleasant element in Jerry’s wines (Spain). However, if a significant amount is present in dining wine, it is considered a deficiency.

Acetaldehyde (Wikipedia)

Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3CHO, sometimes abbreviated by chemists as MeCHO (Me = methyl). It is a colorless liquid or gas, boiling near room temperature. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol consumption. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body.

Acetaldehyde
Lewis structure of acetaldehyde
Skeletal structure of acetaldehyde
Ball-and-stick model
Space-filling model
Names
Preferred IUPAC name
Acetaldehyde
Systematic IUPAC name
Ethanal
Other names
Acetic aldehyde
Ethyl aldehyde
Acetylaldehyde
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.761 Edit this at Wikidata
EC Number
  • 200-836-8
KEGG
RTECS number
  • AB1925000
UNII
  • InChI=1S/C2H4O/c1-2-3/h2H,1H3 checkY
    Key: IKHGUXGNUITLKF-UHFFFAOYSA-N checkY
  • InChI=1/C2H4O/c1-2-3/h2H,1H3
    Key: IKHGUXGNUITLKF-UHFFFAOYAB
  • O=CC
  • CC=O
Properties
C2H4O
Molar mass 44.053 g·mol−1
Appearance Colourless gas or liquid
Odor Ethereal
Density 0.784 g·cm−3 (20 °C)

0.7904–0.7928 g·cm−3 (10 °C)

Melting point −123.37 °C (−190.07 °F; 149.78 K)
Boiling point 20.2 °C (68.4 °F; 293.3 K)
miscible
Solubility miscible with ethanol, ether, benzene, toluene, xylene, turpentine, acetone
slightly soluble in chloroform
log P -0.34
Vapor pressure 740 mmHg (20 °C)
Acidity (pKa) 13.57 (25 °C, H2O)
-.5153−6 cm3/g
1.3316
Viscosity 0.21 mPa-s at 20 °C (0.253 mPa-s at 9.5 °C)
Structure
trigonal planar (sp2) at C1
tetrahedral (sp3) at C2
2.7 D
Thermochemistry
89 J·mol−1·K−1
160.2 J·mol−1·K−1
−192.2 kJ·mol−1
-127.6 kJ·mol−1
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
potential occupational carcinogen
GHS labelling:
GHS02: FlammableGHS07: Exclamation markGHS08: Health hazard
H224, H319, H335, H351
P210, P261, P281, P305+P351+P338
NFPA 704 (fire diamond)
3
4
3
Flash point −39.00 °C; −38.20 °F; 234.15 K
175.00 °C; 347.00 °F; 448.15 K
Explosive limits 4.0–60%
Lethal dose or concentration (LD, LC):
1930 mg/kg (rat, oral)
13,000 ppm (rat),
17,000 ppm (hamster),
20,000 ppm (rat)
NIOSH (US health exposure limits):
PEL (Permissible)
200 ppm (360 mg/m3)
IDLH (Immediate danger)
2000 ppm
Safety data sheet (SDS) HMDB
Related compounds
Related aldehydes
Formaldehyde
Propionaldehyde
Related compounds
Ethylene oxide
Supplementary data page
Acetaldehyde (data page)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

The International Agency for Research on Cancer (IARC) has listed acetaldehyde as a Group 1 carcinogen. Acetaldehyde is "one of the most frequently found air toxins with cancer risk greater than one in a million".