MELTING, BOILING, TRIPLE, AND CRITICAL POINTS
AND DENSITIES OF THE ELEMENTS
is table summarizes the signicant points on the phase diagrams for the elements. When reliable data are available, values
are given for the solid-liquid-gas triple-point temperature and
pressure; normal melting point at 101.325 kPa pressure; normal
boiling point; and critical temperature and pressure. All temperatures are on the ITS-90 scale. e column denitions for the table
are as follows.
Column heading
Name
Formula
tmp
tbp
ρ
ttp
ptp
tc
pc
Denition
Element name; common phase names are in
parentheses if more than one allotrope is included
Formula; for elements normally occuring as diatomic
gases, the molecular formula is given
Normal melting point, in °C at 101.325 kPa pressure;
the notation “trans” in the melting point column
indicates the temperature of the transition to the
crystalline form immediately below that entry;
transition temperatures between allotropic forms are
included for several elements
Normal boiling point, in °C; an “sp” notation in the
boiling point column indicates a sublimation point,
where the vapor pressure of the solid phase reaches
101.325 kPa (1 atm)
Density (mass per unit volume), in g cm-3; the
temperature in °C is indicated by a superscript;
values refer to the liquid or solid phase, and all values
are true densities, not specic gravities; the number
of decimal places gives a rough estimate of the
accuracy of the value
Solid-liquid-gas triple-point temperature, in °C
Solid-liquid-gas triple-point pressure, in kPa
Critical temperature, in °C
Critical pressure, in MPa
An asterisk* indicates an extrapolated or estimated value. e
major data sources are listed below.
References
1. e International Temperature Scale of 1990, Metrologia 27, 3, 1990;
errata in Metrologia 27, 107, 1990. <https://doi.org/10.1088/00261394/27/1/002>
2. Bedford, R. E., Bonnier, G., Maas, H., and Pavese, F., Metrologia 33,
133, 1996. <https://doi.org/10.1088/0026-1394/33/2/3>
3. Lemmon, E. W., Huber, M. L., and McLinden, M. O., NIST Standard Reference Database 23: Reference Fluid ermodynamic and
Transport Properties-REFPROP, Version 9.0, National Institute
of Standards and Technology, Standard Reference Data Program,
Gaithersburg, MD, 2007 (http://www.nist.gov/nist23.cfm). [Ar, F, H,
He, Kr, N, Ne, O, Xe]
4. Dinsdale, A.T., SGTE Data for Pure Elements, CALPHAD 15, 317425, 1991. <https://doi.org/10.1016/0364-5916(91)90030-N>
5. Landolt-Börnstein, Numerical Data and Functional Relationships
in Science and Technology, New Series, IV/19A, “ermodynamic
Properties of Inorganic Materials compiled by SGTE,” SpringerVerlag, Heidelberg; Part 1, 1999.
6. Chase, M. W., NIST-JANAF ermochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph No. 9, 1998.
7. Gurvich, L. V., Veyts, I. V., and Alcock, C. B., ermodynamic Properties of Individual Substances, Fourth Edition, Hemisphere Publishing Corp., New York, 1989.
8. Greenwood, N. N., and Earnshaw, A., Chemistry of the Elements,
Second Edition, Butterworth-Heinemann, Oxford, 1997.
9. Hultgren, R. R., Selected Values of ermodynamic Properties of the
Elements, American Society of Metals, 1973.
10. Geiger, F., Busse, C. A., and Loehrke, R. I., Int. J. ermophys. 8, 425,
1987. [Boiling points of In, Ag, Ga, Cu, Sn, and Au] <https://doi.
org/10.1007/BF00567103>
11. Velasco, S., Roman, F. L., White, J. A., and Mulero, A., Fluid Phase
Equilib. 244, 11, 2006. [Critical temperatures of Ag, Be, Bi, Ge, Fe,
Mn, Te] <https://doi.org/10.1016/j.uid.2006.03.017>
12. Gustafson, P., Carbon 24, 169, 1986. [Graphite and diamond]
<https://doi.org/10.1016/0008-6223(86)90113-2>
13. Michels, A., and Prins, C., Physica 28, 101, 1962. [Triple point of Ar,
Kr, Xe] <https://doi.org/10.1016/0031-8914(62)90096-4>
Melting, Boiling, Triple, and Critical Point Temperatures and Densities of the Elements
Name
Actinium
Aluminum
Americium
Antimony (gray)
Argon
Arsenic (gray)
Astatine
Barium
Berkelium (β form)
Beryllium
Bismuth
Boron
Bromine
Cadmium
Calcium
Californium
Carbon (graphite)
Carbon (diamond)
Cerium
Cesium
Formula
Ac
Al
Am
Sb
Ar
As
At
Ba
Bk
Be
Bi
B
Br2
Cd
Ca
Cf
C
C
Ce
Cs
tmp/ºC
1050
660.323
1176
630.628
-189.34
817
302
727
986
1287
271.402
2077
-7.2
321.069
842
900
4489 tp (10.3 MPa)
4440 (12.4 GPa)**
799
28.5
tbp/ºC
ρ/g cm-3
≈3200
2519
≈2011
1587
-185.848
616 sp
10
2.70
12
6.68
1.395-185.8 liq
5.75
≈1845
3.62
13.25
1.85
9.79
2.34
3.1028
8.69
1.54
15.1
2.2
3.513
6.770
1.873
2468
1564
4000
58.8
767
1484
3825 sp
3443
671
ttp/ºC
ptp/kPa
tc/ºC
pc/MPa
6427 *
-189.3442
817
68.89
3700
-122.463
1400
4.863
22.3
4932 *
4347 *
-7.25
5.879
4489
10300
315
10.34
1665
9.4
Name
Chlorine
Chromium
Cobalt
Copper
Curium
Dysprosium
Einsteinium
Erbium
Europium
Fermium
Fluorine
Francium
Gadolinium
Gallium
Germanium
Gold
Hafnium
Helium
Holmium
Hydrogen
Indium
Iodine
Iridium
Iron
Krypton
Lanthanum
Lawrencium
Lead
Lithium
Lutetium
Magnesium
Manganese
Mendelevium
Mercury
Molybdenum
Neodymium
Neon
Neptunium
Nickel
Niobium
Nitrogen
Nobelium
Osmium
Oxygen
Palladium
Phosphorus (white)
Phosphorus (red)
Platinum
Plutonium
Polonium
Potassium
Praseodymium
Promethium
Protactinium
Radium
Radon
Rhenium
Rhodium
Rubidium
Ruthenium
Samarium
Formula
Cl2
Cr
Co
Cu
Cm
Dy
Es
Er
Eu
Fm
F2
Fr
Gd
Ga
Ge
Au
Hf
He
Ho
H2
In
I2
Ir
Fe
Kr
La
Lr
Pb
Li
Lu
Mg
Mn
Md
Hg
Mo
Nd
Ne
Np
Ni
Nb
N2
No
Os
O2
Pd
P
P
Pt
Pu
Po
K
Pr
Pm
Pa
Ra
Rn
Re
Rh
Rb
Ru
Sm
tmp/ºC
-101.5
1907
1495
1084.62
1345
1412
860
1529
822
1527
-219.67
≈21
1313
29.7646
938.25
1064.18
2233
1472
-259.16
156.5985
113.7
2446
1538
-157.37
920
1627
327.462
180.50
1663
650
1246
827
-38.8290
2622
1016
-248.59
644
1455
2477
-210.0
827
3033
-218.79
1554.8
44.15
579.2
1768.2
640
254
63.5
931
1042
1572
696
-71
3185
1963
39.30
2333
1072
tbp/ºC
-34.04
2671
2927
2560
ρ/g cm-3
2567
1.565-34.0 liq
7.15
8.86
8.96
13.51
8.55
2868
1529
9.07
5.24
-188.11
1.5127-188.1 liq
3273
2229
2833
2836
4600
-268.928
2700
-252.879
2027
184.4
4428
2861
-153.415
3464
7.90
5.91
5.3234
19.3
13.3
0.1250-268.9 liq
8.80
0.07083-252.9 liq
7.31
4.933
22.56220
7.87
2.417-153.4 liq
6.15
1749
1342
3402
1090
2061
11.3
0.534
9.84
1.74
7.3
356.619
4639
3074
-246.046
≈3902
2913
4741
-195.795
13.5335925 liq
10.2
7.01
1.207-246.0 liq
20.2
8.90
8.57
0.8061-195.8 liq
5008
-182.962
2963
280.5
431 sp
3825
3228
962
759
3520
≈3000
22.58720
1.141-183.0 liq
12.0
1.823
2.16
21.5
19.7
9.20
0.89
6.77
7.26
15.4
5
0.00907425 gas
20.8
12.4
1.53
12.1
7.52
-61.7
5590
3695
688
4147
1794
ttp/ºC
ptp/kPa
tc/ºC
pc/MPa
-100.98
1.392
143.9
7.991
-219.67
90
-128.74
5.1724
29.7666
9529 *
-270.973
5.043
-267.9550
0.22746
-259.3467
156.5936
113.6
7.041
-240.212
1.2858
12.11
546
-157.375
73.53
9067 *
-63.67
5.525
2950 *
67 *
4052 *
-38.8344
1491
167
-248.5939
43.37
-228.6580
2.6786
-209.999
12.52
-146.958
3.3958
-218.7916
0.1463
-118.569
5.0430
721
721
39.26
1950 *
16 *
104
6.28
1820 *
16 *
Name
Scandium
Selenium (vitreous)
Selenium (gray)
Silicon
Silver
Sodium
Strontium
Sulfur (rhombic)
Sulfur (monoclinic)
Tantalum
Technetium
Tellurium
Terbium
allium
orium
ulium
Tin (gray)
Tin (white)
Titanium
Tungsten
Uranium
Vanadium
Xenon
Ytterbium
Yttrium
Zinc
Zirconium
*
**
Formula
Sc
Se
Se
Si
Ag
Na
Sr
S
S
Ta
Tc
Te
Tb
Tl

Tm
Sn (α)
Sn (β)
Ti
W
U
V
Xe
Yb
Y
Zn
Zr
tmp/ºC
1541
180 trans gray Se
220.8
1414
961.78
97.794
777
95.2 trans monocl
115.21
3017
2157
449.51
1359
304
1750
1545
13.2 trans white Sn
231.928
1670
3414
1135
1910
-111.75
824
1522
419.527
1854
tbp/ºC
ρ/g cm-3
2836
685
685
3265
2162
882.940
1377
444.61
444.61
5455
4262
988
3230
1473
4785
1950
2586
2586
3287
5555
4131
3407
-108.099
1196
3345
907
4406
2.99
4.28
4.809
2.3296
10.5
0.97
2.64
2.07
2.00
16.4
11
6.232
8.23
11.8
11.7
9.32
5.769
7.287
4.506
19.3
19.1
6.0
2.942-108.1 liq
6.90
4.47
7.134
6.52
Extrapolated or estimated value.
is is the estimated diamond-graphite-liquid carbon triple point (Ref. 12).
ttp/ºC
ptp/kPa
tc/ºC
pc/MPa
1493
1493
27.2
6137 *
2300 *
35 *
1041
1041
20.7
2056 *
-111.745
81.77
16.583
5.8420