Melting, Boiling, Triple, and Critical Points of the Elements
This table summarizes the significant points on the phase dia- 3. Lemmon, E. W., Huber, M. L., and McLinden, M. O., NIST Standard
grams for the elements. When reliable date are available, values Reference Database 23: Reference Fluid Thermodynamic and Transport
are given for the solid-liquid-gas triple-point temperature ttp and Properties-REFPROP, Version 9.0, National Institute of Standards and
Technology, Standard Reference Data Program, Gaithersburg, MD, 2007
pressure ptp; normal melting point at 101.325 kPa pressure tm; nor-
(www.nist.gov/nist23.cfm). [Ar, F, H, He, Kr, N, Ne, O, Xe]
mal boiling point tb; and critical temperature tc and pressure pc. All 4. Dinsdale, A.T., “SGTE Data for Pure Elements”, CALPHAD 15, 317-
temperatures are on the ITS-90 scale. 425, 1991.
An “sp” notation in the boiling point column indicates a subli- 5. Landolt-Börnstein, Numerical Data and Functional Relationships
mation point, where the vapor pressure of the solid phase reaches in Science and Technology, New Series, IV/19A, “Thermodynamic
101.325 kPa (1 atm). Transition temperatures between allotropic Properties of Inorganic Materials compiled by SGTE,” Springer-
forms are included for several elements. The notation “tr” in the Verlag, Heidelberg; Part 1, 1999.
melting point column indicates the temperature of the transition 6. Chase, M. W., NIST-JANAF Thermochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph No. 9, 1998.
to the crystalline form immediately below that entry. An asterisk*
7. Gurvich, L. V., Veyts, I. V., and Alcock, C. B., Thermodynamic
indicates an extrapolated or estimated value. Properties of Individual Substances, Fourth Edition, Hemisphere
The major data sources are listed below. Publishing Corp., New York, 1989.
8. Greenwood, N. N., and Earnshaw, A., Chemistry of the Elements,
References Second Edition, Butterworth-Heinemann, Oxford, 1997.
9. Hultgren, R. R., Selected Values of Thermodynamic Properties of the
Elements, American Society of Metals, 1973.
1. “The International Temperature Scale of 1990”, Metrologia 27, 3, 1990; 10. Geiger, F., Busse, C. A., and Loehrke, R. I., Int. J. Thermophys. 8, 425,
errata in Metrologia 27, 107, 1990.
1987. [Boiling points of In, Ag, Ga, Cu, Sn, and Au]
2. Bedford, R. E., Bonnier, G., Maas, H., and Pavese, F., Metrologia 33,
11. Velasco, S., Roman, F. L., White, J. A., and Mulero, A., Fluid Phase Equilib.
133, 1996.
244, 11, 2006. [Critical temperatures of Ag, Be, Bi, Ge, Fe, Mn, Te]
12. Gustafson, P., Carbon 24, 169, 1986. [Graphite and diamond]
13. Michels, A., and Prins, C., Physica 28, 101, 1962. [Triple point of Ar,
Kr, Xe]
Element Symbol ttp/°C ptp/MPa tm/°C tb/°C tc/°C pc/MPa
Actinium Ac 1050 3200*
Aluminum Al 660.323 2519 6427*
Americium Am 1176 2011*
Antimony (gray) Sb 630.628 1587
Argon Ar –189.3442 0.06889 –189.34 –185.848 –122.463 4.863
Arsenic (gray) As 817 3.70 817 616 sp 1400 22.3
Astatine At 302*
Barium Ba 727 1845*
Berkelium (β form) Bk 986
Beryllium Be 1287 2468 4932*
Bismuth Bi 271.406 1564 4347*
Boron B 2077 4000
Bromine Br2 –7.25 0.0058 –7.2 58.8 315 10.34
Cadmium Cd 321.069 767
Calcium Ca 842 1484
Californium Cf 900
Carbon (graphite) C 4489 10.3 3825 sp
Carbon (diamond) C 4440 (12.4 GPa)a
Cerium Ce 799 3443
Cesium Cs 28.5 671 1665 9.4
Chlorine Cl2 –101.5 –34.04 143.8 7.991
Chromium Cr 1907 2671
Cobalt Co 1495 2927
Copper Cu 1084.62 2560
Curium Cm 1345
Dysprosium Dy 1412 2567
Einsteinium Es 860
Erbium Er 1529 2868
Europium Eu 822 1529
Fermium Fm 1527
Fluorine F2 –219.67 0.09 –219.67 –188.11 –128.74 5.1724
Francium Fr 21
Gadolinium Gd 1313 3273
4-121
4-122 Melting, Boiling, Triple, and Critical Points of the Elements
Element Symbol ttp/°C ptp/MPa tm/°C tb/°C tc/°C pc/MPa
Gallium Ga 29.7666 29.7646 2229
Germanium Ge 938.25 2833 9529*
Gold Au 1064.18 2836
Hafnium Hf 2233 4600
Helium He –270.973 0.005043 –268.928 –267.9547 0.22746
Holmium Ho 1472 2700
Hydrogen H2 –259.3467 0.007041 –259.16 –252.879 –240.212 1.2858
Indium In 156.5936 156.60 2027
Iodine I2 113.6 0.01211 113.7 184.4 546
Iridium Ir 2446 4428
Iron Fe 1538 2861 9067*
Krypton Kr –157.375 0.07353 –157.37 –153.415 –63.67 5.525
Lanthanum La 920 3464
Lawrencium Lr 1627
Lead Pb 327.462 1749
Lithium Li 180.50 1342 2950* 67*
Lutetium Lu 1663 3402
Magnesium Mg 650 1090
Manganese Mn 1246 2061 4052*
Mendelevium Md 827
Mercury Hg –38.8344 –38.8290 356.619 1491 167
Molybdenum Mo 2622 4639
Neodymium Nd 1016 3074
Neon Ne –248.594 0.04337 –248.59 –246.046 –228.6582 2.6786
Neptunium Np 644 3902*
Nickel Ni 1455 2913
Niobium Nb 2477 4741
Nitrogen N2 –209.999 0.01252 –210.0 –195.795 –146.958 3.3958
Nobelium No 827
Osmium Os 3033 5008
Oxygen O2 –218.789 0.0001463 –218.79 –182.962 –118.569 5.043
Palladium Pd 1554.8 2963
Phosphorus (white) P 44.15 280.5 721
Phosphorus (red) P 579.2 431 sp 721
Platinum Pt 1768.2 3825
Plutonium Pu 640 3228
Polonium Po 254 962
Potassium K 63.5 759 1950* 16*
Praseodymium Pr 931 3520
Promethium Pm 1042 3000*
Protactinium Pa 1572
Radium Ra 696
Radon Rn –71 –61.7 104 6.28
Rhenium Re 3185 5590
Rhodium Rh 1963 3695
Rubidium Rb 39.26 39.30 688 1820* 16*
Ruthenium Ru 2333 4147
Samarium Sm 1072 1794
Scandium Sc 1541 2836
Selenium (vitreous) Se 180 tr 685 1493
Selenium (gray) Se 220.8 685 1493 27.2
Silicon Si 1414 3265
Silver Ag 961.78 2162 6137*
Sodium Na 97.794 882.940 2300* 35*
Strontium Sr 777 1377
Sulfur (rhombic) S 95.2 tr 444.61 1041 20.7
Sulfur (monoclinic) S 115.21 444.61 1041
Tantalum Ta 3017 5455
Technetium Tc 2157 4262
Tellurium Te 449.51 988 2056*
Terbium Tb 1359 3230
Melting, Boiling, Triple, and Critical Points of the Elements 4-123
Element Symbol ttp/°C ptp/MPa tm/°C tb/°C tc/°C pc/MPa
Thallium Tl 304 1473
Thorium Th 1750 4785
Thulium Tm 1545 1950
Tin (gray) Sn 13.2 tr 2586
Tin (white) Sn 231.928 2586
Titanium Ti 1670 3287
Tungsten W 3414 5555
Uranium U 1135 4131
Vanadium V 1910 3407
Xenon Xe –111.745 0.08177 –111.75 –108.099 16.583 5.842
Ytterbium Yb 824 1196
Yttrium Y 1522 3345
Zinc Zn 419.527 907
Zirconium Zr 1854 4406
* Extrapolated or estimated value
a
This is the estimated diamond-graphite-liquid carbon triple point (Ref. 12).
