potassium

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, 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
Δfgas89.0 ± 0.8kJ/molReviewCox, Wagman, et al., 1984CODATA Review value
Δfgas89.00kJ/molReviewChase, 1998Data last reviewed in December, 1961
Quantity Value Units Method Reference Comment
gas,1 bar160.341 ± 0.003J/mol*KReviewCox, Wagman, et al., 1984CODATA Review value
gas,1 bar160.34J/mol*KReviewChase, 1998Data last reviewed in December, 1961

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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Temperature (K) 1039.54 to 1800.1800. to 6000.
A 20.6612258.70570
B 0.391869-27.38277
C -0.4173446.730509
D 0.145582-0.420844
E 0.003764-25.87921
F 82.8386032.37931
G 185.2650198.3777
H 88.9999688.99996
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in December, 1961 Data last reviewed in December, 1961

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, 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
Δfliquid2.27kJ/molReviewChase, 1998Data last reviewed in December, 1961
Quantity Value Units Method Reference Comment
liquid,1 bar71.40J/mol*KReviewChase, 1998Data last reviewed in December, 1961
Quantity Value Units Method Reference Comment
solid,1 bar64.68 ± 0.20J/mol*KReviewCox, Wagman, et al., 1984CODATA Review value
Quantity Value Units Method Reference Comment
solid64.63J/mol*KReviewChase, 1998Data last reviewed in December, 1961

Liquid 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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Temperature (K) 336.35 to 1039.54
A 40.27113
B -30.54542
C 26.49505
D -5.727854
E -0.063477
F -8.812467
G 127.7614
H 2.270005
ReferenceChase, 1998
Comment Data last reviewed in December, 1961

Solid 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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Temperature (K) 298. to 336.35
A -63.47410
B -3226.340
C 14644.60
D -16229.50
E 16.29410
F 119.6480
G 533.8780
H 0.000000
ReferenceChase, 1998
Comment Data last reviewed in December, 1961

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, 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

Quantity Value Units Method Reference Comment
Tboil1037.KN/AHonig and Kramer, 1969Uncertainty assigned by TRC = 1. K; TRC
Quantity Value Units Method Reference Comment
Ttriple336.35KN/AHonig and Kramer, 1969Uncertainty assigned by TRC = 0.1 K; TRC

Antoine Equation Parameters

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

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Temperature (K) A B C Reference Comment
679.4 to 1033.04.457184691.5824.195Fiock and Rodebush, 1926Coefficents calculated by NIST from author's data.

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, 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: 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.

Individual Reactions

(Potassium ion (1+) • 10potassium) + potassium = (Potassium ion (1+) • 11potassium)

By formula: (K+ • 10K) + K = (K+ • 11K)

Quantity Value Units Method Reference Comment
Δr54.0kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 11potassium) + potassium = (Potassium ion (1+) • 12potassium)

By formula: (K+ • 11K) + K = (K+ • 12K)

Quantity Value Units Method Reference Comment
Δr56.1kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 12potassium) + potassium = (Potassium ion (1+) • 13potassium)

By formula: (K+ • 12K) + K = (K+ • 13K)

Quantity Value Units Method Reference Comment
Δr56.1kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 13potassium) + potassium = (Potassium ion (1+) • 14potassium)

By formula: (K+ • 13K) + K = (K+ • 14K)

Quantity Value Units Method Reference Comment
Δr62.3kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 14potassium) + potassium = (Potassium ion (1+) • 15potassium)

By formula: (K+ • 14K) + K = (K+ • 15K)

Quantity Value Units Method Reference Comment
Δr54.8kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 15potassium) + potassium = (Potassium ion (1+) • 16potassium)

By formula: (K+ • 15K) + K = (K+ • 16K)

Quantity Value Units Method Reference Comment
Δr62.8kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 16potassium) + potassium = (Potassium ion (1+) • 17potassium)

By formula: (K+ • 16K) + K = (K+ • 17K)

Quantity Value Units Method Reference Comment
Δr64.9kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 17potassium) + potassium = (Potassium ion (1+) • 18potassium)

By formula: (K+ • 17K) + K = (K+ • 18K)

Quantity Value Units Method Reference Comment
Δr67.4kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 18potassium) + potassium = (Potassium ion (1+) • 19potassium)

By formula: (K+ • 18K) + K = (K+ • 19K)

Quantity Value Units Method Reference Comment
Δr65.7kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 19potassium) + potassium = (Potassium ion (1+) • 20potassium)

By formula: (K+ • 19K) + K = (K+ • 20K)

Quantity Value Units Method Reference Comment
Δr72.4kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 20potassium) + potassium = (Potassium ion (1+) • 21potassium)

By formula: (K+ • 20K) + K = (K+ • 21K)

Quantity Value Units Method Reference Comment
Δr54.0kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 21potassium) + potassium = (Potassium ion (1+) • 22potassium)

By formula: (K+ • 21K) + K = (K+ • 22K)

Quantity Value Units Method Reference Comment
Δr59.8kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 22potassium) + potassium = (Potassium ion (1+) • 23potassium)

By formula: (K+ • 22K) + K = (K+ • 23K)

Quantity Value Units Method Reference Comment
Δr56.9kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 23potassium) + potassium = (Potassium ion (1+) • 24potassium)

By formula: (K+ • 23K) + K = (K+ • 24K)

Quantity Value Units Method Reference Comment
Δr61.9kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 9potassium) + potassium = (Potassium ion (1+) • 10potassium)

By formula: (K+ • 9K) + K = (K+ • 10K)

Quantity Value Units Method Reference Comment
Δr54.8kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 2potassium) + potassium = (Potassium ion (1+) • 3potassium)

By formula: (K+ • 2K) + K = (K+ • 3K)

Quantity Value Units Method Reference Comment
Δr43.5kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 3potassium) + potassium = (Potassium ion (1+) • 4potassium)

By formula: (K+ • 3K) + K = (K+ • 4K)

Quantity Value Units Method Reference Comment
Δr64.9kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 4potassium) + potassium = (Potassium ion (1+) • 5potassium)

By formula: (K+ • 4K) + K = (K+ • 5K)

Quantity Value Units Method Reference Comment
Δr52.3kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 5potassium) + potassium = (Potassium ion (1+) • 6potassium)

By formula: (K+ • 5K) + K = (K+ • 6K)

Quantity Value Units Method Reference Comment
Δr72.4kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 6potassium) + potassium = (Potassium ion (1+) • 7potassium)

By formula: (K+ • 6K) + K = (K+ • 7K)

Quantity Value Units Method Reference Comment
Δr56.1kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 7potassium) + potassium = (Potassium ion (1+) • 8potassium)

By formula: (K+ • 7K) + K = (K+ • 8K)

Quantity Value Units Method Reference Comment
Δr87.0kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

(Potassium ion (1+) • 8potassium) + potassium = (Potassium ion (1+) • 9potassium)

By formula: (K+ • 8K) + K = (K+ • 9K)

Quantity Value Units Method Reference Comment
Δr48.1kJ/molPDissBrechignac, Cahuzac, et al., 1990gas phase

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Notes

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

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

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

Honig and Kramer, 1969
Honig, R.E.; Kramer, D.A., Vapor pressure data for the solid and liquid elements, RCA Rev., 1969, 1969, 285. [all data]

Fiock and Rodebush, 1926
Fiock, E.F.; Rodebush, W.H., The Vapor Pressures and Thermal Properties of Potassium and Some Alkali Halides, J. Am. Chem. Soc., 1926, 48, 10, 2522-2528, https://doi.org/10.1021/ja01421a006 . [all data]

Brechignac, Cahuzac, et al., 1990
Brechignac, C.; Cahuzac, P.; Carlier, F.; De Frutos, M.; Leyniger, J., Cohesive Energies of (K)n+ 5<n<200 from Photoevaporation Experiments, J. Chem. Phys., 1990, 93, 10, 7449, https://doi.org/10.1063/1.459418 . [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References