Paraldehyde
- Formula: C6H12O3
- Molecular weight: 132.1577
- IUPAC Standard InChIKey: SQYNKIJPMDEDEG-UHFFFAOYSA-N
- CAS Registry Number: 123-63-7
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Stereoisomers:
- Other names: 1,3,5-Trioxane, 2,4,6-trimethyl-; s-Trioxane, 2,4,6-trimethyl-; s-Trimethyltrioxymethylene; Acetaldehyde trimer; Elaldehyde; Paraacetaldehyde; Paracetaldehyde; Paral; Pcho; 1,3,5-Trimethyl-2,4,6-trioxane; 2,4,6-Trimethyl-s-trioxane; 2,4,6-Trimethyl-1,3,5-trioxane; 2,4,6-Trimethyl-1,3,5-trioxan; Paraldehyd; Paraldeide; Triacetaldehyde; 2,4,6-Trimethyl-1,3,5-trioxaan; 2,4,6-Trimethyl-1,3,5-trioxacyclohexane; 2,4,6-Trimetil-1,3,5-triossano; Rcra waste number U182; UN 1264; Trimethyl trioxane; NSC 9799
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -636. ± 3. | kJ/mol | Ccb | Pihlaja and Tuomi, 1970 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 374.4 ± 5.0 | J/mol*K | N/A | Clegg G.A., 1969 | GT |
Condensed phase thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°liquid | -681.8 ± 2.6 | kJ/mol | Ccb | Pihlaja and Tuomi, 1970 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -3394.2 ± 2.6 | kJ/mol | Ccb | Pihlaja and Tuomi, 1970 | Corresponding ΔfHºliquid = -681.82 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -3389. | kJ/mol | Ccb | Fletcher, Mortimer, et al., 1959 | Corresponding ΔfHºliquid = -687.0 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -3390. ± 2. | kJ/mol | Ccb | Cass, Springall, et al., 1955 | Corresponding ΔfHºliquid = -686.2 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 289.4 | J/mol*K | N/A | Clegg and Melia, 1969 | Extrapolation below 80 K, 61.1 J/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
257.3 | 298.15 | Clegg and Melia, 1969 | T = 80 to 310 K.; DH |
254.0 | 306.6 | Phillip, 1939 | DH |
250.2 | 298. | von Reis, 1881 | T = 293 to 400 K.; DH |
Phase change data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 401.15 | K | N/A | Grimm and Patrick, 1923 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tboil | 397.15 | K | N/A | Paul and Schantz, 1919 | Uncertainty assigned by TRC = 1. K; TRC |
Tboil | 395. | K | N/A | Hollmann, 1903 | Uncertainty assigned by TRC = 1. K; TRC |
Tboil | 397.2 | K | N/A | Von Reis, 1881 | Uncertainty assigned by TRC = 1.5 K; TRC |
Tboil | 396.5 | K | N/A | Bruhl, 1880 | Uncertainty assigned by TRC = 1. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 284.15 | K | N/A | Biltz, Fischer, et al., 1930 | Uncertainty assigned by TRC = 1. K; TRC |
Tfus | 285.65 | K | N/A | Cooper, 1928 | Uncertainty assigned by TRC = 0.2 K; TRC |
Tfus | 286. | K | N/A | Louguinine and Dupont, 1911 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tfus | 285.70 | K | N/A | Hollmann, 1903 | Uncertainty assigned by TRC = 0.1 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 285.7 | K | N/A | Clegg and Melia, 1969 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.1 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 563. | K | N/A | Hollmann, 1903 | Uncertainty assigned by TRC = 4. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 45.8 | kJ/mol | N/A | Pihlaja and Tuomi, 1970 | DRB |
ΔvapH° | 41. ± 0.4 | kJ/mol | V | Fletcher, Mortimer, et al., 1959 | ALS |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
41.5 | 338. | A | Stephenson and Malanowski, 1987 | Based on data from 323. to 396. K.; AC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
13.52 | 285.7 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.81 | 142.7 | Domalski and Hearing, 1996 | CAL |
5.24 | 147.5 | ||
47.32 | 285.7 |
Enthalpy of phase transition
ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.2577 | 142.7 | crystaline, IV | crystaline, III | Clegg and Melia, 1969 | DH |
0.7731 | 147.5 | crystaline, III | crystaline, II | Clegg and Melia, 1969 | H and S of transition for c,II/c,I at 230.3 K has been added into H and S of fusion at 285.7 K.; DH |
13.520 | 285.7 | crystaline, I | liquid | Clegg and Melia, 1969 | DH |
Entropy of phase transition
ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
1.81 | 142.7 | crystaline, IV | crystaline, III | Clegg and Melia, 1969 | DH |
5.24 | 147.5 | crystaline, III | crystaline, II | Clegg and Melia, 1969 | H; DH |
47.32 | 285.7 | crystaline, I | liquid | Clegg and Melia, 1969 | DH |
Reaction thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
By formula: 3C2H4O = C6H12O3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -87. ± 6. | kJ/mol | Cm | Krasnov, Ozherel'eva, et al., 1983 | liquid phase; solvent: Nonaqueous; Trimerization |
ΔrH° | -98.1 | kJ/mol | Eqk | Busfield, Lee, et al., 1973 | gas phase |
By formula: C6H12O3 = 3C2H4O
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 98.1 | kJ/mol | Eqk | Busfield, Lee, et al., 1973 | gas phase; At 292-313 K |
IR Spectrum
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Data compiled by: Coblentz Society, Inc.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Mass spectrum (electron ionization)
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Gas Chromatography, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
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Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
NIST MS number | 20876 |
Gas Chromatography
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Packed | SE-30 | 150. | 755. | Tiess, 1984 | Ar, Gas Chrom Q (80-100 mesh); Column length: 3. m |
Packed | Apiezon L | 120. | 729. | Bogoslovsky, Anvaer, et al., 1978 | Celite 545 |
Packed | Apiezon L | 160. | 734. | Bogoslovsky, Anvaer, et al., 1978 | Celite 545 |
Normal alkane RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Packed | SE-30 | 786. | MHA, 9999 | Nitrogen, Chromosorb G AW DMCS (80-100 mesh); Column length: 2. m; Tstart: 100. C; Tend: 300. C |
Capillary | MDN-5 | 781. | van Loon, Linssen, et al., 2005 | 60. m/0.25 mm/0.25 μm, He, 40. C @ 4. min, 4. K/min, 270. C @ 5. min |
Capillary | DB-5 | 776. | Berdague, Denoyer, et al., 1991 | 60. m/0.32 mm/1.0 μm, He, 3. K/min; Tstart: 40. C; Tend: 240. C |
Normal alkane RI, non-polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | SE-30 | 763. | Vinogradov, 2004 | Program: not specified |
Capillary | SPB-1 | 767. | Flanagan, Streete, et al., 1997 | 60. m/0.53 mm/5. μm, He; Program: 40C(6min) => 5C/min => 80C => 10C/min => 200C |
Capillary | SPB-1 | 767. | Strete, Ruprah, et al., 1992 | 60. m/0.53 mm/5.0 μm, Helium; Program: 40 0C (6 min) 5 0C/min -> 80 0C 10 0C/min -> 200 0C |
Capillary | SPB-1 | 771. | Strete, Ruprah, et al., 1992 | 60. m/0.53 mm/5.0 μm, Helium; Program: not specified |
Capillary | OV-1 | 786. | Ramsey and Flanagan, 1982 | Program: not specified |
Normal alkane RI, polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | FFAP | 1070. | Vernin, Metzger, et al., 1993 | 60. C @ 8. min, 2. K/min; Column length: 50. m; Column diameter: 0.22 mm; Tend: 230. C |
Normal alkane RI, polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Carbowax 20M | 1069. | Vinogradov, 2004 | Program: not specified |
Capillary | Carbowax 20M | 1069. | Ramsey and Flanagan, 1982 | Program: not specified |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Pihlaja and Tuomi, 1970
Pihlaja, K.; Tuomi, M.,
Bond-Bond interactions in organic oxygen compounds. Part II. Anomalous stablization in cis-2,4,6-trimethyl-1,3,5-trioxane,
Suom. Kemistil., 1970, 43, 224-226. [all data]
Clegg G.A., 1969
Clegg G.A.,
Thermodynamics of polymerization of heterocyclic compounds. Part IV. The heat capacity, entropy, enthalpy and free energy of paraldehyde,
Makromol. Chem., 1969, 123, 194-202. [all data]
Fletcher, Mortimer, et al., 1959
Fletcher, S.E.; Mortimer, C.T.; Springall, H.D.,
Heats of combustion and molecular structure. Part VII. 1:3-dioxa- and 1:3:5-trioxa-cycloalkanes,
J. Chem. Soc., 1959, 580-584. [all data]
Cass, Springall, et al., 1955
Cass, R.C.; Springall, H.D.; White, T.R.,
The anomalous heat of combustion of paraldehyde,
Chem. Ind. (London), 1955, 387-388. [all data]
Clegg and Melia, 1969
Clegg, G.A.; Melia, T.P.,
Thermodynamics of polymerization of heterocyclic compounds. Part IV. The heat capacity, entropy, enthalpy and free energy of paraldehyde,
Makromol. Chem., 1969, 123, 194-202. [all data]
Phillip, 1939
Phillip, N.M.,
Adiabatic and isothermal compressibilities of liquids,
Proc. Indian Acad. Sci., 1939, A9, 109-120. [all data]
von Reis, 1881
von Reis, M.A.,
Die specifische Wärme flüssiger organischer Verbindungen und ihre Beziehung zu deren Moleculargewicht,
Ann. Physik [3], 1881, 13, 447-464. [all data]
Grimm and Patrick, 1923
Grimm, F.V.; Patrick, W.A.,
The Dielectric Constastants of Organic Liquids at the Boilin Point,
J. Am. Chem. Soc., 1923, 45, 2794. [all data]
Paul and Schantz, 1919
Paul, T.; Schantz, K.,
The boiling point as indicator of purity and a new apparatus for its determination without thermometer correction.,
Arch. Pharm. (Weinheim, Ger.), 1919, 257, 87. [all data]
Hollmann, 1903
Hollmann, R.,
Physical and natural equilibria between the modifications of aldehyde,
Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1903, 43, 129-59. [all data]
Von Reis, 1881
Von Reis, M.A.,
IV. The Specific Heat of Liquid Organic Compounds and its Relation to Molecular Weight.,
Ann. Phys. (Leipzig), 1881, 13, 447. [all data]
Bruhl, 1880
Bruhl, J.W.,
The Chemical Constitution of Organic Compounds in Relation to their Density and their Ability to Propagate Light,
Justus Liebigs Ann. Chem., 1880, 203, 1. [all data]
Biltz, Fischer, et al., 1930
Biltz, W.; Fischer, W.; Wunnenberg, E.,
Molecular and Atomic Volumes. The Volume Requirements of Crystalline Organic Compounds and Low Temperatures,
Z. Phys. Chem., Abt. A, 1930, 151, 13-55. [all data]
Cooper, 1928
Cooper, D.L.,
The Heat Cpacities of Acetaldehyde and Paraldehyde, and the Heat of Transformation of Acetaldehyde into Paraldehyde,
Proc. Trans. N. S. Inst. Sci., Pt. 1, 1928, 17. 82-90. [all data]
Louguinine and Dupont, 1911
Louguinine, W.; Dupont, G.,
The heat of fusion of substances which melt at ordinary temperatures.,
Bull. Soc. Chim. Fr., 1911, 9, 219-224. [all data]
Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw,
Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2
. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [all data]
Krasnov, Ozherel'eva, et al., 1983
Krasnov, V.L.; Ozherel'eva, N.K.; Trub, E.P.; Tsvetkov, V.G.; Bodrikov, I.V.,
Trimerization of aldehydes under the action of sulfur dioxide,
J. Gen. Chem. USSR, 1983, 53, 2135-2138. [all data]
Busfield, Lee, et al., 1973
Busfield, W.K.; Lee, R.M.; Merifold, D.,
Gas phase equilibrium between acetaldehyde and paraldehyde, thermodynamic values for the trimerisation of acetaldehyde and the polymerisability of paraldehyde,
J. Chem. Soc. Faraday Trans. 1, 1973, 69, 936-940. [all data]
Tiess, 1984
Tiess, D.,
Gaschromatographische Retentionsindices von 125 leicht- bis mittelflüchtigen organischen Substanzen toxikologisch-analytischer Relevanz auf SE-30,
Wiss. Z. Wilhelm-Pieck-Univ. Rostock Math. Naturwiss. Reihe, 1984, 33, 6-9. [all data]
Bogoslovsky, Anvaer, et al., 1978
Bogoslovsky, Yu.N.; Anvaer, B.I.; Vigdergauz, M.S.,
Chromatographic constants in gas chromatography (in Russian), Standards Publ. House, Moscow, 1978, 192. [all data]
MHA, 9999
MHA, Directorate of ForensicScience.,
Forensic Toxicology, 9999. [all data]
van Loon, Linssen, et al., 2005
van Loon, W.A.M.; Linssen, J.P.H.; Legger, A.; Posthumus, M.A.; Voragen, A.G.J.,
Identification and olfactometry of French fries flavour extracted at mouth conditions,
Food Chem., 2005, 90, 3, 417-425, https://doi.org/10.1016/j.foodchem.2004.05.005
. [all data]
Berdague, Denoyer, et al., 1991
Berdague, J.-L.; Denoyer, C.; Le Quéré, J.-L.; Semon, E.,
Volatile components of dry-cured ham,
J. Agric. Food Chem., 1991, 39, 7, 1257-1261, https://doi.org/10.1021/jf00007a012
. [all data]
Vinogradov, 2004
Vinogradov, B.A.,
Production, composition, properties and application of essential oils, 2004, retrieved from http://viness.narod.ru. [all data]
Flanagan, Streete, et al., 1997
Flanagan, R.J.; Streete, P.J.; Ramsey, J.D.,
Volatile Substance Abuse, UNODC Technical Series, No 5, United Nations, Office on Drugs and Crime, Vienna International Centre, PO Box 500, A-1400 Vienna, Austria, 1997, 56, retrieved from http://www.odccp.org/pdf/technicalseries1997-01-011.pdf. [all data]
Strete, Ruprah, et al., 1992
Strete, P.J.; Ruprah, M.; Ramsey, J.D.; Flanagan, R.J.,
Detection and identification of volatile substances by headspace capillary gas chromatography to aid the diagnosis of acute poisoning,
Analyst, 1992, 117, 7, 1111-1127, https://doi.org/10.1039/an9921701111
. [all data]
Ramsey and Flanagan, 1982
Ramsey, J.D.; Flanagan, R.J.,
Detection and Identification of Volatile Organic Compounds in Blood by Headspace Gas Chromatography as an Aid to the Diagnosis of Solvent Abuse,
J. Chromatogr., 1982, 240, 2, 423-444, https://doi.org/10.1016/S0021-9673(00)99622-5
. [all data]
Vernin, Metzger, et al., 1993
Vernin, G.; Metzger, J.; Sultan, A.A.M.; El-Shafei, A.K.; Párkányi, C.,
Heterocyclic compounds in model systems for the Maillard reaction. Reactions of aldehydes with ammonium sulfide in the presence or absence of acetoin,
Am. Chem. Soc. Symp. Ser., 1993, 528, 36-55. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid S°gas Entropy of gas at standard conditions S°liquid Entropy of liquid at standard conditions Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrH° Enthalpy of reaction at standard conditions ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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