Carboxylic acidIn organic chemistry, a carboxylic acid is a polar, organic acid that contains a carboxyl group (−C(=O)−OH) attached to an R-group. The general formula of a carboxylic acid is often written as R−COOH or R−CO2H, sometimes as R−C(O)OH, with R referring to an organyl group (e.g., alkyl, alkenyl, aryl), or hydrogen, or other groups. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids.
MonomerA monomer ( ; , "one" + , "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or two- or three-dimensional network in a process called polymerization.IUPAC definitionMonomer molecule: A molecule which can undergo polymerization, thereby contributing constitutional units to the essential structure of a macromolecule.AnhydrousA substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achieve perfect dryness; anhydrous compounds gradually absorb water from the atmosphere so they must be stored carefully. Substances that contain water or its constituent elements are called hydrates.
Acetic acidChemical acid found in vinegarSample of acetic acid in a reagent bottleNames Preferred IUPAC nameAcetic acidSystematic IUPAC nameEthanoic acidOther names Vinegar (when diluted); Hydrogen acetate; Methanecarboxylic acid; Ethylic acidIdentifiers CAS Number64-19-73D model (JSmol)Interactive imageAbbreviations AcOH Beilstein Reference506007 ChEBICHEBI:15366ChEMBLChEMBL539ChemSpider171DrugBankDB03166ECHA InfoCard100.000.528EC Number200-580-7E numberE260 (preservatives)Gmelin Reference1380 IUPHAR/BPS1058KEGGC00033D00010MeSHAcetic+acidPubChemCID176RTECS numberAF1225000UNIIQ40Q9N063PUN number2789 CompTox Dashboard(EPA)DTXSID5024394InChIInChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4)Key: QTBSBXVTEAMEQO-UHFFFAOYSA-NSMILESCC(O)=OProperties Chemical formulaCH3COOH Molar mass60.052 g·mol Appearance Colourless liquid OdorOverpowering vinegar-like Density1.049 g/cm (liquid); 1.27 g/cm (solid) Melting point16 to 17 °C; 61 to 62 °F; 289 to 290 K Boiling point118 to 119 °C; 244 to 246 °F; 391 to 392 K Critical point (T, P) 593 K (320 °C), 57.8 bar Solubility in waterMisciblelog P−0.28 Vapor pressure1.54653947 kPa (20 °C) 11.6 mmHg (20 °C) Acidity (pKa) 4.756 Conjugate baseAcetateMagnetic susceptibility (χ)−31.54·10 cm/mol Refractive index (nD)1.371 (VD = 18.19) Viscosity1.22 mPa s 1.22 cP Dipole moment1.74 D Thermochemistry Heat capacity(C)123.1 J/(K⋅mol) Std molarentropy(S298)158.0 J/(K⋅mol) Std enthalpy offormation(ΔfH298)−483.88–483.16 kJ/mol Std enthalpy ofcombustion(ΔcH298)−875.50–874.82 kJ/mol-876.1 kJ/mol Enthalpy of fusion(ΔfHfus)11.7 kJ/mol Enthalpy of vaporization(ΔfHvap)23.7 kJ/mol Pharmacology ATC codeG01AD02 (WHO) S02AA10 (WHO) Legal statusAU: S2 (Pharmacy medicine) / Schedule 6, Schedule 5, Schedule 2 Appendix E, clause 3 Appendix F, clause 4Hazards GHS labelling: PictogramsSignal wordDangerHazard statementsH226, H314Precautionary statementsP280, P305+P351+P338, P310NFPA 704 (fire diamond) 320Flash point40 °C (104 °F; 313 K) Autoignitiontemperature427 °C (801 °F; 700 K) Explosive limits4–16% Lethal dose or concentration (LD, LC): LD50 (median dose)3.31 g/kg, oral (rat) LC50 (median concentration)5620 ppm (mouse, 1 h)16000 ppm (rat, 4 h) NIOSH (US health exposure limits): PEL (Permissible)TWA 10 ppm (25 mg/m) REL (Recommended)TWA 10 ppm (25 mg/m) ST 15 ppm (37 mg/m) IDLH (Immediate danger)50 ppm Related compounds Related carboxylic acidsFormic acidPropionic acidRelated compoundsAcetaldehydeAcetamideAcetic anhydrideChloroacetic acidAcetyl chlorideGlycolic acidEthyl acetatePotassium acetateSodium acetateThioacetic acidSupplementary data page Acetic acid (data page)Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).N verify ( ?)
Molecular entityIn chemistry and physics, a molecular entity, or chemical entity, is "any constitutionally or isotopically distinct atom, molecule, ion, ion pair, radical, radical ion, complex, conformer, etc., identifiable as a separately distinguishable entity".
Chemical speciesA chemical species is a type of matter that displays a specific, uniquely identifying, set of properties. A systematic chemical name can be used to refer to a chemical species.In practice, chemists identify chemical species by differentiating between features of molecular structure that affect the interactions between molecules of a species and between molecules of different species.Niels BjerrumNiels Janniksen Bjerrum (11 March 1879 – 30 September 1958) was a Danish chemist. Niels Bjerrum was the son of ophthalmologist Jannik Petersen Bjerrum, and started to study at the University of Copenhagen in 1897. He received his Master's degree in 1902 and his Doctor's degree in 1908, and did research in coordination complex chemistry under Sophus Mads Jørgensen.
IonAn ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons.
Chemical bondA chemical bond is the association of atoms or ions to form molecules, crystals, and other structures. The bond may result from the electrostatic force between oppositely charged ions, as in ionic bonds; the sharing of electrons, as in covalent bonds; or some combination of these effects.
ChemistryScientific study of matter's behavior and propertiesImages relating to the six main branches of chemistry, clockwise from the upper left : a BeF₂ glass network (inorganic chemistry), a caffeine molecule (organic chemistry), a reaction coordinate diagram (physical chemistry), a proton NMR spectrum (analytical chemistry), the RGS4 protein (biochemistry), and a glowstick using chemiluminescence (applied chemistry).Chemistry is the scientific study of the properties and behavior of matter.
Dissociation (chemistry)Dissociation in chemistry is a general process in which molecules (or ionic compounds such as salts, or complexes) separate or split into other things such as atoms, ions, or radicals, usually in a reversible manner. For instance, when an acid dissolves in water, a covalent bond between an electronegative atom and a hydrogen atom is broken by heterolytic fission, which gives a proton (H+) and a negative ion. Dissociation is the opposite of association or recombination.
ExcimerAn excimer (originally short for excited dimer) is a short-lived polyatomic molecule formed from two species that do not form a stable molecule in the ground state. In this case, formation of molecules is possible only if such atom is in an electronic excited state. Heteronuclear molecules and molecules that have more than two species are also called exciplex molecules (originally short for excited complex).*As an Amazon Associate I earn from qualifying purchases.