Hydrogen cyanide

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Quantity Value Units Method Reference Comment
Δfgas32.299kcal/molReviewChase, 1998Data last reviewed in December, 1969
Quantity Value Units Method Reference Comment
gas,1 bar48.236cal/mol*KReviewChase, 1998Data last reviewed in December, 1969

Gas Phase Heat Capacity (Shomate Equation)

Cp° = A + B*t + C*t2 + D*t3 + E/t2
H° − H°298.15= A*t + B*t2/2 + C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 − E/(2*t2) + G
    Cp = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. to 1200.1200. to 6000.
A 7.81399012.51560
B 5.3996301.329660
C -1.044250-0.227826
D -0.0974420.013554
E -0.067495-1.807860
F 29.5126924.82130
G 55.7504158.51931
H 32.3000032.30000
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in December, 1969 Data last reviewed in December, 1969

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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: Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
liquid27.010cal/mol*KN/AGiauque and Ruehrwein, 1939 

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
16.97300.Giauque and Ruehrwein, 1939T = 15 to 300 K.

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
DH - Eugene S. Domalski and Elizabeth D. Hearing
AC - William E. Acree, Jr., James S. Chickos

Quantity Value Units Method Reference Comment
Tboil299.0 ± 0.5KAVGN/AAverage of 15 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus260. ± 1.KAVGN/AAverage of 13 out of 14 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple259.86KN/AGiauque and Ruehrwein, 1939, 2Crystal phase 1 phase; Uncertainty assigned by TRC = 0.02 K; TRC

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
6.0270298.85N/AGiauque and Ruehrwein, 1939P = 101.325 kPa.; DH
6.72274.AStephenson and Malanowski, 1987Based on data from 259. to 299. K.; AC
6.64313.AStephenson and Malanowski, 1987Based on data from 298. to 457. K.; AC
6.72272.N/AIwasaki and Date, 1975Based on data from 257. to 315. K.; AC
6.69277.N/ALewis and Schutz, 1934Based on data from 259. to 294. K.; AC
6.64282.N/APerry and Porter, 1926Based on data from 265. to 300. K.; AC
6.72272.N/ASinozaki, Hara, et al., 1926Based on data from 257. to 319. K.; AC
6.50303.MMSinozaki, Hara, et al., 1926Based on data from 256. to 319. K.; AC

Entropy of vaporization

ΔvapS (cal/mol*K) Temperature (K) Reference Comment
20.17298.85Giauque and Ruehrwein, 1939P; DH

Antoine Equation Parameters

log10(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Temperature (K) A B C Reference Comment
256.73 to 319.384.668461340.791-11.592Sinozaki, Hara, et al., 1926Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

ΔsubH (kcal/mol) Temperature (K) Method Reference Comment
8.51248.N/AStephenson and Malanowski, 1987Based on data from 236. to 259. K.; AC
8.99228.AStull, 1947Based on data from 202. to 254. K.; AC

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
2.009259.90Giauque and Ruehrwein, 1939DH

Entropy of fusion

ΔfusS (cal/mol*K) Temperature (K) Reference Comment
7.729259.90Giauque and Ruehrwein, 1939DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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.

Reactions 1 to 50

CN- + Hydrogen cyanide = (CN- • Hydrogen cyanide)

By formula: CN- + CHN = (CN- • CHN)

Quantity Value Units Method Reference Comment
Δr21.7 ± 3.5kcal/molIMRELarson and McMahon, 1987gas phase; B,M
Δr20.0 ± 2.0kcal/molEstLarson and McMahon, 1984gas phase; B
Δr20.7kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr20.7kcal/molPHPMSMeot-ner, 1988gas phase; M,B,B,M
Quantity Value Units Method Reference Comment
Δr20.6cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr20.6cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Δr20.6cal/mol*KPHPMSMeot-ner, 1988gas phase; M
Δr26.9cal/mol*KN/ALarson and McMahon, 1987gas phase; switching reaction,Thermochemical ladder(H2O), Entropy change calculated or estimated; Payzant, Yamdagni, et al., 1971; M
Quantity Value Units Method Reference Comment
Δr14.5 ± 1.0kcal/molTDAsMeot-ner, 1988gas phase; B
Δr13.7 ± 2.3kcal/molIMRELarson and McMahon, 1987gas phase; B,M
Δr14.5 ± 1.6kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

Fluorine anion + Hydrogen cyanide = (Fluorine anion • Hydrogen cyanide)

By formula: F- + CHN = (F- • CHN)

Quantity Value Units Method Reference Comment
Δr39.5 ± 2.0kcal/molIMRELarson and McMahon, 1983gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B,M
Quantity Value Units Method Reference Comment
Δr22.2cal/mol*KN/ALarson and McMahon, 1983gas phase; switching reaction(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M
Quantity Value Units Method Reference Comment
Δr32.9 ± 2.0kcal/molIMRELarson and McMahon, 1983gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B,M

Lithium ion (1+) + Hydrogen cyanide = (Lithium ion (1+) • Hydrogen cyanide)

By formula: Li+ + CHN = (Li+ • CHN)

Quantity Value Units Method Reference Comment
Δr36.4kcal/molICRWoodin and Beauchamp, 1978gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M
Δr36.kcal/molICRStaley and Beauchamp, 1975gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 extrapolated; M
Quantity Value Units Method Reference Comment
Δr25.cal/mol*KN/AWoodin and Beauchamp, 1978gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M
Quantity Value Units Method Reference Comment
Δr28.kcal/molICRWoodin and Beauchamp, 1978gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M

Chlorine anion + Hydrogen cyanide = (Chlorine anion • Hydrogen cyanide)

By formula: Cl- + CHN = (Cl- • CHN)

Quantity Value Units Method Reference Comment
Δr21.8 ± 1.0kcal/molTDAsMeot-ner, 1988gas phase; B,B,M
Δr21.0 ± 2.0kcal/molIMRELarson and McMahon, 1984, 2gas phase; B,M
Quantity Value Units Method Reference Comment
Δr18.9cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Δr23.7cal/mol*KN/ALarson and McMahon, 1984, 3gas phase; switching reaction(Cl-)t-C4H9OH, Entropy change calculated or estimated; French, Ikuta, et al., 1982; M
Quantity Value Units Method Reference Comment
Δr16.2 ± 1.6kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B
Δr16.1 ± 1.0kcal/molTDAsMeot-ner, 1988gas phase; B
Δr13.9 ± 2.0kcal/molIMRELarson and McMahon, 1984, 2gas phase; B,M

CN- + Hydrogen cation = Hydrogen cyanide

By formula: CN- + H+ = CHN

Quantity Value Units Method Reference Comment
Δr349.8 ± 1.0kcal/molCIDTAkin and Ervin, 2006gas phase; B
Δr350.50 ± 0.17kcal/molD-EABradforth, Kim, et al., 1993gas phase; B
Δr351.1 ± 2.1kcal/molG+TSBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Δr342.5 ± 1.1kcal/molH-TSAkin and Ervin, 2006gas phase; B
Δr343.17 ± 0.27kcal/molH-TSBradforth, Kim, et al., 1993gas phase; B
Δr343.8 ± 2.0kcal/molIMREBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B

HCO2 anion + Hydrogen cyanide = (HCO2 anion • Hydrogen cyanide)

By formula: CHO2- + CHN = (CHO2- • CHN)

Quantity Value Units Method Reference Comment
Δr22.0kcal/molPHPMSMeot-ner, 1988gas phase; M,B,M
Quantity Value Units Method Reference Comment
Δr22.cal/mol*KN/AMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M
Δr21.4cal/mol*KPHPMSMeot-ner, 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr15.6 ± 1.6kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy of 22.0 eu assumed.; B

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
11.8473.PHPMSMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M

(HCO2 anion • Hydrogen cyanide) + Hydrogen cyanide = (HCO2 anion • 2Hydrogen cyanide)

By formula: (CHO2- • CHN) + CHN = (CHO2- • 2CHN)

Quantity Value Units Method Reference Comment
Δr17.8kcal/molPHPMSMeot-ner, 1988gas phase; M,B,M
Quantity Value Units Method Reference Comment
Δr22.cal/mol*KN/AMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M
Δr23.6cal/mol*KPHPMSMeot-ner, 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr10.70kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy estimated; B

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
9.6350.PHPMSMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M

(NH4+ • 3Hydrogen cyanide • Ammonia) + Hydrogen cyanide = (NH4+ • 4Hydrogen cyanide • Ammonia)

By formula: (H4N+ • 3CHN • H3N) + CHN = (H4N+ • 4CHN • H3N)

Quantity Value Units Method Reference Comment
Δr8.6kcal/molPHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated, T = 392 in paper is error; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KN/ADeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated, T = 392 in paper is error; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
2.7292.PHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated, T = 392 in paper is error; M

(Chlorine anion • 8Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 9Hydrogen cyanide)

By formula: (Cl- • 8CHN) + CHN = (Cl- • 9CHN)

Quantity Value Units Method Reference Comment
Δr7.5 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy estimated; B,M
Quantity Value Units Method Reference Comment
Δr25.cal/mol*KN/AMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr0.10kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy estimated; B

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
3.2171.PHPMSMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M

(MeCO2 anion • 4Hydrogen cyanide) + Hydrogen cyanide = (MeCO2 anion • 5Hydrogen cyanide)

By formula: (C2H3O2- • 4CHN) + CHN = (C2H3O2- • 5CHN)

Quantity Value Units Method Reference Comment
Δr9.8 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy estimated; B,M
Quantity Value Units Method Reference Comment
Δr25.cal/mol*KN/AMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr2.40kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy estimated; B

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
4.5213.PHPMSMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M

(CN- • 6Hydrogen cyanide) + Hydrogen cyanide = (CN- • 7Hydrogen cyanide)

By formula: (CN- • 6CHN) + CHN = (CN- • 7CHN)

Quantity Value Units Method Reference Comment
Δr7.6 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy estimated; B,M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KN/AMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr1.60kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; Entropy estimated; B

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
3.0238.PHPMSMeot-ner, Cybulski, et al., 1988gas phase; Entropy change calculated or estimated; M

(CN- • 2Hydrogen cyanide) + Hydrogen cyanide = (CN- • 3Hydrogen cyanide)

By formula: (CN- • 2CHN) + CHN = (CN- • 3CHN)

Quantity Value Units Method Reference Comment
Δr12.6kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr12.6kcal/molPHPMSMeot-ner, 1988gas phase; M,B,M
Quantity Value Units Method Reference Comment
Δr21.2cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr21.2cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Δr21.2cal/mol*KPHPMSMeot-ner, 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr6.30kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(CN- • 3Hydrogen cyanide) + Hydrogen cyanide = (CN- • 4Hydrogen cyanide)

By formula: (CN- • 3CHN) + CHN = (CN- • 4CHN)

Quantity Value Units Method Reference Comment
Δr10.9kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr10.9kcal/molPHPMSMeot-ner, 1988gas phase; M,B,M
Quantity Value Units Method Reference Comment
Δr24.8cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr24.8cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Δr24.8cal/mol*KPHPMSMeot-ner, 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr3.50kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(CN- • Hydrogen cyanide) + Hydrogen cyanide = (CN- • 2Hydrogen cyanide)

By formula: (CN- • CHN) + CHN = (CN- • 2CHN)

Quantity Value Units Method Reference Comment
Δr16.4kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr16.4kcal/molPHPMSMeot-ner, 1988gas phase; M,B,M
Quantity Value Units Method Reference Comment
Δr21.8cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr21.8cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Δr21.8cal/mol*KPHPMSMeot-ner, 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr9.90kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

CH2N+ + Hydrogen cyanide = (CH2N+ • Hydrogen cyanide)

By formula: CH2N+ + CHN = (CH2N+ • CHN)

Quantity Value Units Method Reference Comment
Δr26.1kcal/molPHPMSSpeller and Meot-Ner (Mautner), 1985gas phase; ΔrH, ΔrS too small compared with other nitrile dimers; M
Δr30.0kcal/molPHPMSMeot-Ner (Mautner), 1978gas phase; M
Quantity Value Units Method Reference Comment
Δr23.0cal/mol*KPHPMSSpeller and Meot-Ner (Mautner), 1985gas phase; ΔrH, ΔrS too small compared with other nitrile dimers; M
Δr32.cal/mol*KPHPMSMeot-Ner (Mautner), 1978gas phase; M

(CN- • Water • 2Hydrogen cyanide) + Water = (CN- • 2Water • 2Hydrogen cyanide)

By formula: (CN- • H2O • 2CHN) + H2O = (CN- • 2H2O • 2CHN)

Quantity Value Units Method Reference Comment
Δr8.9 ± 1.0kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; Entropy estimated; B,M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr2.9 ± 1.4kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; Entropy estimated; B

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
3.7262.PHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M

(CN- • 3Hydrogen cyanide) + Water = (CN- • Water • 3Hydrogen cyanide)

By formula: (CN- • 3CHN) + H2O = (CN- • H2O • 3CHN)

Quantity Value Units Method Reference Comment
Δr9.4 ± 1.0kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; Entropy estimated; B,M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr3.4 ± 1.4kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; Entropy estimated; B

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
4.2262.PHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M

(CH2N+ • Hydrogen cyanide • Water) + Hydrogen cyanide = (CH2N+ • 2Hydrogen cyanide • Water)

By formula: (CH2N+ • CHN • H2O) + CHN = (CH2N+ • 2CHN • H2O)

Quantity Value Units Method Reference Comment
Δr15.6kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n, Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr24.cal/mol*KN/AMeot-Ner (Mautner) and Speller, 1989gas phase; n, Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr8.4kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n, Entropy change calculated or estimated; M

(NH4+ • Ammonia • 2Hydrogen cyanide) + Ammonia = (NH4+ • 2Ammonia • 2Hydrogen cyanide)

By formula: (H4N+ • H3N • 2CHN) + H3N = (H4N+ • 2H3N • 2CHN)

Quantity Value Units Method Reference Comment
Δr12.9kcal/molPHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KN/ADeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
6.6315.PHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M

(NH4+ • Hydrogen cyanide • 2Ammonia) + Hydrogen cyanide = (NH4+ • 2Hydrogen cyanide • 2Ammonia)

By formula: (H4N+ • CHN • 2H3N) + CHN = (H4N+ • 2CHN • 2H3N)

Quantity Value Units Method Reference Comment
Δr11.2kcal/molPHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KN/ADeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
4.9315.PHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M

(CN- • 4Hydrogen cyanide) + Hydrogen cyanide = (CN- • 5Hydrogen cyanide)

By formula: (CN- • 4CHN) + CHN = (CN- • 5CHN)

Quantity Value Units Method Reference Comment
Δr9.8 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Δr9.8kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr20.2cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Δr20.2cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr3.80kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(NH4+ • Hydrogen cyanide) + Ammonia = (NH4+ • Ammonia • Hydrogen cyanide)

By formula: (H4N+ • CHN) + H3N = (H4N+ • H3N • CHN)

Quantity Value Units Method Reference Comment
Δr18.8kcal/molPHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr22.cal/mol*KN/ADeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
9.4429.PHPMSDeakyne, Knuth, et al., 1994gas phase; Entropy change calculated or estimated; M

Bromine anion + Hydrogen cyanide = (Bromine anion • Hydrogen cyanide)

By formula: Br- + CHN = (Br- • CHN)

Quantity Value Units Method Reference Comment
Δr19.4 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Δr16.0 ± 2.0kcal/molEstLarson and McMahon, 1984gas phase; Extrapolated from other halide data; B
Quantity Value Units Method Reference Comment
Δr19.8cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr13.5 ± 1.6kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

C4H9O2+ + Hydrogen cyanide = (C4H9O2+ • Hydrogen cyanide)

By formula: C4H9O2+ + CHN = (C4H9O2+ • CHN)

Quantity Value Units Method Reference Comment
Δr19.0kcal/molPHPMSSpeller and Meot-Ner (Mautner), 1985gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr23.cal/mol*KN/ASpeller and Meot-Ner (Mautner), 1985gas phase; Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
7.9455.PHPMSSpeller and Meot-Ner (Mautner), 1985gas phase; Entropy change calculated or estimated; M

C3H7+ + Hydrogen cyanide = (C3H7+ • Hydrogen cyanide)

By formula: C3H7+ + CHN = (C3H7+ • CHN)

Quantity Value Units Method Reference Comment
Δr39.6kcal/molPHPMSMeot-Ner (Mautner) and Sieck, 1991gas phase; condensation; M
Δr30.8kcal/molPHPMSMeot-Ner (Mautner), 1978gas phase; forms i-C3H7NCH+; M
Quantity Value Units Method Reference Comment
Δr45.2cal/mol*KPHPMSMeot-Ner (Mautner) and Sieck, 1991gas phase; condensation; M
Δr32.cal/mol*KPHPMSMeot-Ner (Mautner), 1978gas phase; forms i-C3H7NCH+; M

HS- + Hydrogen cyanide = (HS- • Hydrogen cyanide)

By formula: HS- + CHN = (HS- • CHN)

Quantity Value Units Method Reference Comment
Δr21.0 ± 1.0kcal/molIMREMeot-ner, 1988gas phase; See also H2S..CN-; B,M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KPHPMSMeot-ner, 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr15.0 ± 1.0kcal/molIMREMeot-ner, 1988gas phase; See also H2S..CN-; B

NH4+ + Hydrogen cyanide = (NH4+ • Hydrogen cyanide)

By formula: H4N+ + CHN = (H4N+ • CHN)

Quantity Value Units Method Reference Comment
Δr21.9kcal/molPHPMSDeakyne, Knuth, et al., 1994gas phase; M
Δr20.5kcal/molPHPMSSpeller and Meot-Ner (Mautner), 1985gas phase; M
Quantity Value Units Method Reference Comment
Δr23.4cal/mol*KPHPMSDeakyne, Knuth, et al., 1994gas phase; M
Δr20.2cal/mol*KPHPMSSpeller and Meot-Ner (Mautner), 1985gas phase; M

(CN- • Water • Hydrogen cyanide) + Water = (CN- • 2Water • Hydrogen cyanide)

By formula: (CN- • H2O • CHN) + H2O = (CN- • 2H2O • CHN)

Quantity Value Units Method Reference Comment
Δr9.5 ± 1.0kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; B,M
Quantity Value Units Method Reference Comment
Δr17.5cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr4.2 ± 1.4kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; B

(CN- • 2Hydrogen cyanide) + Water = (CN- • Water • 2Hydrogen cyanide)

By formula: (CN- • 2CHN) + H2O = (CN- • H2O • 2CHN)

Quantity Value Units Method Reference Comment
Δr7.7 ± 1.0kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; B,M
Quantity Value Units Method Reference Comment
Δr12.5cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr4.0 ± 1.4kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; B

(CN- • Hydrogen cyanide) + Water = (CN- • Water • Hydrogen cyanide)

By formula: (CN- • CHN) + H2O = (CN- • H2O • CHN)

Quantity Value Units Method Reference Comment
Δr12.4 ± 1.0kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; B,M
Quantity Value Units Method Reference Comment
Δr19.7cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr6.5 ± 1.4kcal/molTDAsMeot-Ner (Mautner) M. and Speller, 1989gas phase; B

(Chlorine anion • 7Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 8Hydrogen cyanide)

By formula: (Cl- • 7CHN) + CHN = (Cl- • 8CHN)

Quantity Value Units Method Reference Comment
Δr8.2 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr27.4cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr0.0 ± 2.2kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(CN- • Hydrogen cyanide • 2Water) + Hydrogen cyanide = (CN- • 2Hydrogen cyanide • 2Water)

By formula: (CN- • CHN • 2H2O) + CHN = (CN- • 2CHN • 2H2O)

Quantity Value Units Method Reference Comment
Δr12.6kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
7.4262.PHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M

(CN- • 2Hydrogen cyanide • Water) + Hydrogen cyanide = (CN- • 3Hydrogen cyanide • Water)

By formula: (CN- • 2CHN • H2O) + CHN = (CN- • 3CHN • H2O)

Quantity Value Units Method Reference Comment
Δr12.3kcal/molPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KPHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
7.1262.PHPMSMeot-Ner (Mautner) and Speller, 1989gas phase; n; M

(Chlorine anion • 2Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 3Hydrogen cyanide)

By formula: (Cl- • 2CHN) + CHN = (Cl- • 3CHN)

Quantity Value Units Method Reference Comment
Δr13.6 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr21.4cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr7.20kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Chlorine anion • 3Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 4Hydrogen cyanide)

By formula: (Cl- • 3CHN) + CHN = (Cl- • 4CHN)

Quantity Value Units Method Reference Comment
Δr11.2 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr23.4cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr4.20kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Chlorine anion • Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 2Hydrogen cyanide)

By formula: (Cl- • CHN) + CHN = (Cl- • 2CHN)

Quantity Value Units Method Reference Comment
Δr17.9 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr22.7cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr11.10kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Iodide • 2Hydrogen cyanide) + Hydrogen cyanide = (Iodide • 3Hydrogen cyanide)

By formula: (I- • 2CHN) + CHN = (I- • 3CHN)

Quantity Value Units Method Reference Comment
Δr11.2 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr21.0cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr4.90kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Bromine anion • 2Hydrogen cyanide) + Hydrogen cyanide = (Bromine anion • 3Hydrogen cyanide)

By formula: (Br- • 2CHN) + CHN = (Br- • 3CHN)

Quantity Value Units Method Reference Comment
Δr12.8 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr21.9cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr6.30kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Bromine anion • 3Hydrogen cyanide) + Hydrogen cyanide = (Bromine anion • 4Hydrogen cyanide)

By formula: (Br- • 3CHN) + CHN = (Br- • 4CHN)

Quantity Value Units Method Reference Comment
Δr10.4 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr22.1cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr3.80kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Chlorine anion • 4Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 5Hydrogen cyanide)

By formula: (Cl- • 4CHN) + CHN = (Cl- • 5CHN)

Quantity Value Units Method Reference Comment
Δr8.8 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr21.3cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr2.50kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Chlorine anion • 5Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 6Hydrogen cyanide)

By formula: (Cl- • 5CHN) + CHN = (Cl- • 6CHN)

Quantity Value Units Method Reference Comment
Δr8.7 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr24.3cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr1.50kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Chlorine anion • 6Hydrogen cyanide) + Hydrogen cyanide = (Chlorine anion • 7Hydrogen cyanide)

By formula: (Cl- • 6CHN) + CHN = (Cl- • 7CHN)

Quantity Value Units Method Reference Comment
Δr7.9 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr23.1cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr1.00kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Iodide • 3Hydrogen cyanide) + Hydrogen cyanide = (Iodide • 4Hydrogen cyanide)

By formula: (I- • 3CHN) + CHN = (I- • 4CHN)

Quantity Value Units Method Reference Comment
Δr9.2 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr20.3cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr3.20kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Iodide • 4Hydrogen cyanide) + Hydrogen cyanide = (Iodide • 5Hydrogen cyanide)

By formula: (I- • 4CHN) + CHN = (I- • 5CHN)

Quantity Value Units Method Reference Comment
Δr8.6 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr22.9cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr1.80kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Iodide • 5Hydrogen cyanide) + Hydrogen cyanide = (Iodide • 6Hydrogen cyanide)

By formula: (I- • 5CHN) + CHN = (I- • 6CHN)

Quantity Value Units Method Reference Comment
Δr7.4 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr19.9cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr1.50kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Iodide • 6Hydrogen cyanide) + Hydrogen cyanide = (Iodide • 7Hydrogen cyanide)

By formula: (I- • 6CHN) + CHN = (I- • 7CHN)

Quantity Value Units Method Reference Comment
Δr7.4 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr19.9cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr1.50kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Iodide • 7Hydrogen cyanide) + Hydrogen cyanide = (Iodide • 8Hydrogen cyanide)

By formula: (I- • 7CHN) + CHN = (I- • 8CHN)

Quantity Value Units Method Reference Comment
Δr6.8 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr21.2cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr0.50kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Iodide • Hydrogen cyanide) + Hydrogen cyanide = (Iodide • 2Hydrogen cyanide)

By formula: (I- • CHN) + CHN = (I- • 2CHN)

Quantity Value Units Method Reference Comment
Δr13.2 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr20.0cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr7.20kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Bromine anion • 4Hydrogen cyanide) + Hydrogen cyanide = (Bromine anion • 5Hydrogen cyanide)

By formula: (Br- • 4CHN) + CHN = (Br- • 5CHN)

Quantity Value Units Method Reference Comment
Δr8.1 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr18.5cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr2.60kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

(Bromine anion • Hydrogen cyanide) + Hydrogen cyanide = (Bromine anion • 2Hydrogen cyanide)

By formula: (Br- • CHN) + CHN = (Br- • 2CHN)

Quantity Value Units Method Reference Comment
Δr16.3 ± 1.0kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B,M
Quantity Value Units Method Reference Comment
Δr22.7cal/mol*KPHPMSMeot-ner, Cybulski, et al., 1988gas phase; M
Quantity Value Units Method Reference Comment
Δr9.50kcal/molTDAsMeot-ner, Cybulski, et al., 1988gas phase; B

Henry's Law data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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: Rolf Sander

Henry's Law constant (water solution)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)

H (mol/(kg*bar)) d(ln(kH))/d(1/T) (K) Method Reference Comment
7.5 XN/AValue given here as quoted by missing citation.
12.5000.LN/A 
9.3 RN/A 

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to CHN+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)13.60 ± 0.01eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)170.4kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity162.9kcal/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
0.00156N/AArd, Garrett, et al., 2009B
>1.00171EIAETsuda, Yokohata, et al., 1971From CH3CN; G3MP2B3 calculations indicate that the anion is unbound by ca. 1 eV. Possibly C2H3- instead.; B

Ionization energy determinations

IE (eV) Method Reference Comment
13.71EILageot, 1972LLK
13.59 ± 0.01PIDibeler and Liston, 1968RDSH
13.60 ± 0.01PEBaker and Turner, 1968RDSH
13.73 ± 0.09EIVarsel, Morrell, et al., 1960RDSH
13.7 ± 0.1EIKusch, Hustrulid, et al., 1937RDSH
13.61PEKreile, Schweig, et al., 1982Vertical value; LBLHLM
13.607 ± 0.002PEFridh and Asbrink, 1975Vertical value; LLK
13.60PEPotts and Williams, 1974Vertical value; LLK
13.61 ± 0.01PEFrost, Lee, et al., 1973Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C+23.8 ± 0.5?EIKusch, Hustrulid, et al., 1937RDSH
CH+21.8 ± 0.5NEIKusch, Hustrulid, et al., 1937RDSH
CN+19.43 ± 0.01HPIBerkowitz, Chupka, et al., 1969RDSH
CN+19.40 ± 0.02HPIDibeler and Liston, 1968RDSH
CN+20.1 ± 0.2HEIKusch, Hustrulid, et al., 1937RDSH
H+15.18 ± 0.02CN-PIBerkowitz, Chupka, et al., 1969RDSH
H+19.00 ± 0.01CNPIBerkowitz, Chupka, et al., 1969RDSH
NH+24.9 ± 0.5CEIKusch, Hustrulid, et al., 1937RDSH
N+25.6 ± 0.5CHEIKusch, Hustrulid, et al., 1937RDSH

De-protonation reactions

CN- + Hydrogen cation = Hydrogen cyanide

By formula: CN- + H+ = CHN

Quantity Value Units Method Reference Comment
Δr349.8 ± 1.0kcal/molCIDTAkin and Ervin, 2006gas phase; B
Δr350.50 ± 0.17kcal/molD-EABradforth, Kim, et al., 1993gas phase; B
Δr351.1 ± 2.1kcal/molG+TSBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Δr342.5 ± 1.1kcal/molH-TSAkin and Ervin, 2006gas phase; B
Δr343.17 ± 0.27kcal/molH-TSBradforth, Kim, et al., 1993gas phase; B
Δr343.8 ± 2.0kcal/molIMREBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), 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: Coblentz Society, Inc.

Spectrum

A digitized version of this spectrum is not currently available.

Additional Data

View scan of original (hardcopy) spectrum.

Owner COBLENTZ SOCIETY
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Source reference COBLENTZ NO. 10480
Date Not specified, most likely prior to 1982
Instrument Not specified, most likely a prism, grating, or hybrid spectrometer.
Data processing (NO SPECTRUM, ONLY SCANNED IMAGE IS AVAILABLE)

This IR spectrum is from the Coblentz Society's evaluated infrared reference spectra collection.


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, 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 11

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Giauque and Ruehrwein, 1939
Giauque, W.F.; Ruehrwein, R.A., The entropy of hydrogen cyanide. Heat capacity, heat of vaporization and vapor pressure. Hydrogen bond polymerization of the gas in chains of indefinite length, J. Am. Chem. Soc., 1939, 61, 2626-2633. [all data]

Giauque and Ruehrwein, 1939, 2
Giauque, W.F.; Ruehrwein, R.A., The Entropy of Hydrogen Cyanide. Heat Capacity, Heat of Vaporization and Vapor Pressure. Hydrogen Bond Polymerization of the Gas in Chains of Indefinite Length., J. Am. Chem. Soc., 1939, 61, 2626. [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]

Iwasaki and Date, 1975
Iwasaki, H.; Date, K., Koatsu Gasu, 1975, 12, 374. [all data]

Lewis and Schutz, 1934
Lewis, Gilbert N.; Schutz, Philip W., THE VAPOR PRESSURE OF LIQUID AND SOLID DEUTOCYANIC ACID, J. Am. Chem. Soc., 1934, 56, 4, 1002-1002, https://doi.org/10.1021/ja01319a514 . [all data]

Perry and Porter, 1926
Perry, J.H.; Porter, Frank, THE VAPOR PRESSURES OF SOLID AND LIQUID HYDROGEN CYANIDE 1, J. Am. Chem. Soc., 1926, 48, 2, [299]-302, https://doi.org/10.1021/ja01413a001 . [all data]

Sinozaki, Hara, et al., 1926
Sinozaki, Heima; Hara, Ryozaburo; Mitsukuri, Shinroku, THE VAPOUR PRESSURES OF HYDROGEN CYANIDE, Bull. Chem. Soc. Jpn., 1926, 1, 4, 59-61, https://doi.org/10.1246/bcsj.1.59 . [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Larson and McMahon, 1987
Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. The energetics of interaction between cyanide ion and bronsted acids, J. Am. Chem. Soc., 1987, 109, 6230. [all data]

Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B., Gas phase bihalide and pseudohalide ions. An ICR determination of hydrogen bond energies in XHY- species (X,Y = F, Cl, Br, CN), Inorg. Chem., 1984, 23, 2029. [all data]

Meot-Ner (Mautner) and Speller, 1989
Meot-Ner (Mautner), M.; Speller, C.V., Multicomponent Cluster Ions.3. Comparative Stabilities of Cationic and Anionic Hydrogen Bonded Networks. Mixed Clusters of Water and Hydrogen Cyanide, J. Phys. Chem., 1989, 93, 6580. [all data]

Meot-ner, 1988
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Notes

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