Standard state (English Wikipedia)

Analysis of information sources in references of the Wikipedia article "Standard state" in English language version.

Last modified: 21:52:14, 15 September 2026 (UTC)

Ref.Un. Ref.Website

Global rank English rank

87doi.org

2^nd place

54unicode.org

691^st place

581^st place

44iupac.org

1,291^st place

1,832^nd place

32thoughtco.com

2,170^th place

1,937^th place

21libretexts.org

4,683^rd place

3,565^th place

11engineeringtoolbox.com

low place

11springer.com

182^nd place

172^nd place

11osti.gov

2,098^th place

1,146^th place

11universitypressscholarship.com

8,662^nd place

5,532^nd place

11openstax.org

8,731^st place

6,059^th place

doi.org (Global: 2^nd place; English: 2^nd place)

IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard state". doi:10.1351/goldbook.S05925
IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard conditions for gases". doi:10.1351/goldbook.S05910
IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard solution". doi:10.1351/goldbook.S05924
IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard pressure". doi:10.1351/goldbook.S05921
Rard, Joseph A.; Wolery, Thomas J. (2007). "The Standard Chemical-Thermodynamic Properties of Phosphorus and Some of its Key Compounds and Aqueous Species: An Evaluation of Differences between the Previous Recommendations of NBS/NIST and CODATA". Journal of Solution Chemistry. 36 (11–12): 1585–1599. doi:10.1007/s10953-007-9205-7. OSTI 920864. Retrieved 24 December 2023. Although white phosphorus is not the thermodynamically stable allotrope, the red and black forms are difficult to prepare in pure form, which makes them less suitable for quantitative thermodynamic measurements.
Sherwood, Dennis; Dalby, Paul (2018). Modern Thermodynamics for Chemists and Biochemists. Oxford Scholarship Online. doi:10.1093/oso/9780198782957.003.0023. ISBN 978-0-19-878295-7. Retrieved 18 May 2021.
Savara, Aditya (2013). "Standard States for Adsorption on Solid Surfaces: 2D Gases, Surface Liquids, and Langmuir Adsorbates". J. Phys. Chem. C. 117 (30): 15710–15715. doi:10.1021/jp404398z.

engineeringtoolbox.com (Global: low place; English: low place)

Toolbox, Engineering (2017). "Standard state and enthalpy of formation, Gibbs free energy of formation, entropy and heat capacity". Engineering ToolBox – Resources, Tools and Basic Information for Engineering and Design of Technical Applications!. www.EngineeringToolBox.com. Retrieved 2019-12-27.

iupac.org (Global: 1,291^st place; English: 1,832^nd place)

goldbook.iupac.org

IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard state". doi:10.1351/goldbook.S05925
IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard conditions for gases". doi:10.1351/goldbook.S05910
IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard solution". doi:10.1351/goldbook.S05924
IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "standard pressure". doi:10.1351/goldbook.S05921

libretexts.org (Global: 4,683^rd place; English: 3,565^th place)

chem.libretexts.org

"Activities and their Effects on Equilibria". Chemistry LibreTexts. 29 January 2016.

openstax.org (Global: 8,731^st place; English: 6,059^th place)

Flowers, Paul; Theopold, Klaus; Langley, Richard; Robinson, William R.; Frantz, Don; Hooker, Paul; Kaminski, George; Look, Jennifer; Martinez, Carol; Eklund, Andrew; Blaser, Mark; Sorensen, Tom; Soult, Allison; Milliken, Troy; Moravec, Vicki; Powell, Jason; El-Giar, Emad; Bott, Simon; Carpenetti, Don (14 February 2019). "5.3 Enthalpy". Chemistry 2e. Open Stax. Retrieved 9 April 2022. We will include a superscripted "o" in the enthalpy change symbol to designate standard state.

osti.gov (Global: 2,098^th place; English: 1,146^th place)

Rard, Joseph A.; Wolery, Thomas J. (2007). "The Standard Chemical-Thermodynamic Properties of Phosphorus and Some of its Key Compounds and Aqueous Species: An Evaluation of Differences between the Previous Recommendations of NBS/NIST and CODATA". Journal of Solution Chemistry. 36 (11–12): 1585–1599. doi:10.1007/s10953-007-9205-7. OSTI 920864. Retrieved 24 December 2023. Although white phosphorus is not the thermodynamically stable allotrope, the red and black forms are difficult to prepare in pure form, which makes them less suitable for quantitative thermodynamic measurements.

springer.com (Global: 182^nd place; English: 172^nd place)

link.springer.com

Rard, Joseph A.; Wolery, Thomas J. (2007). "The Standard Chemical-Thermodynamic Properties of Phosphorus and Some of its Key Compounds and Aqueous Species: An Evaluation of Differences between the Previous Recommendations of NBS/NIST and CODATA". Journal of Solution Chemistry. 36 (11–12): 1585–1599. doi:10.1007/s10953-007-9205-7. OSTI 920864. Retrieved 24 December 2023. Although white phosphorus is not the thermodynamically stable allotrope, the red and black forms are difficult to prepare in pure form, which makes them less suitable for quantitative thermodynamic measurements.

thoughtco.com (Global: 2,170^th place; English: 1,937^th place)

Helmenstine, Ann Marie (March 8, 2019). "What Are Standard State Conditions? – Standard Temperature and Pressure". Science, Tech, Math > Science. thoughtco.com. Retrieved 2019-12-27.
Helmenstine, Ann Marie (July 6, 2019). "Standard Conditions versus Standard State". Science, Tech, Math > Science. thoughtco.com. Retrieved 2020-09-06.

unicode.org (Global: 691^st place; English: 581^st place)

"Unicode Miscellaneous Symbols Supplement: Range 1CEC0–1CEFF 𜻰 (U+1CEF) MEDIUM SMALL WHITE CIRCLE WITH HORIZONTAL BAR – Used in superscript form to mean standard state (chemistry) → 29B5 ⦵ circle with horizontal bar" (PDF). unicode.org.
"Miscellaneous Mathematical Symbols-B" (PDF). Unicode. 2013. Retrieved 2013-12-19.
Mills, I. M. (1989) "The choice of names and symbols for quantities in chemistry". Journal of Chemical Education (vol. 66, number 11, November 1989 p. 887–889) [Note that Mills refers to the symbol ⊖ (Unicode 2296 "Circled minus" as displayed in https://www.unicode.org/charts/PDF/U2980.pdf) as a plimsoll symbol although it lacks an extending bar in the printed article.]
Soiffer, Neil; Sargent, Murray; Freytag, Asmus (20 October 2023). "Proposal for Ten Chemical Symbols" (PDF). Retrieved 25 December 2023.

universitypressscholarship.com (Global: 8,662^nd place; English: 5,532^nd place)

oxford.universitypressscholarship.com

Sherwood, Dennis; Dalby, Paul (2018). Modern Thermodynamics for Chemists and Biochemists. Oxford Scholarship Online. doi:10.1093/oso/9780198782957.003.0023. ISBN 978-0-19-878295-7. Retrieved 18 May 2021.

Standard state (English Wikipedia)

doi.org (Global: 2nd place; English: 2nd place)

engineeringtoolbox.com (Global: low place; English: low place)

iupac.org (Global: 1,291st place; English: 1,832nd place)

goldbook.iupac.org

libretexts.org (Global: 4,683rd place; English: 3,565th place)

chem.libretexts.org

openstax.org (Global: 8,731st place; English: 6,059th place)

osti.gov (Global: 2,098th place; English: 1,146th place)

springer.com (Global: 182nd place; English: 172nd place)