Noble gas (data page)

This page provides supplementary data about the noble gases, which were excluded from the main article to conserve space and preserve focus. Oganesson mostly not included due to the amount of research known about it.

Physical properties

Solid

Physical property	Helium	Neon	Argon	Krypton	Xenon	Radon
Density, solid at triple point	–	1444	1623	2826	3540	–
Crystal structure	hcp	fcc	fcc	fcc	fcc	fcc

Liquid

Physical property	Helium	Neon	Argon	Krypton	Xenon	Radon
Density, liquid at boiling point and 1 atm	125.0	1207	1393.9	2415	3057	4400
Density, liquid at triple point	–	1247	1415	2451	3084	–
Thermal conductivity, liquid at boiling point	31.4	129.7	121.3	88.3	73.2	–
Dielectric constant	1.057	1.191	1.325	1.664	1.880	—

Gas

Physical property	Helium	Neon	Argon	Krypton	Xenon	Radon
Density, gas at 0 °C and 1 atm	0.1786	0.9002	1.7818	3.708	5.851	9.97
Thermal conductivity at 0 °C	0.1418	0.0461	0.0169	0.00874	0.00506	0.0036
Mean free path at STP	192.66	135.36	68.33	52.34	37.88	–
Solubility in water at 20 °C	8.61	10.5	33.6	59.4	108.1	230
Magnetic susceptibility	−0.0000019	−0.0000072	−0.0000194	−0.000028	−0.000043	–
Heat capacity, C_p, gas at 1 atm	20.78	20.79	20.85	20.95	21.01	21
Sonic velocity at 0 °C and 1 atm	973	433	307.8	213	168	–
Thermal conductivity, gas at 0 °C and 1 atm	141.84	46.07	16.94	8.74	5.06	3.6
Molar refraction	0.521	1.004	4.203	6.397	10.435	–
Dielectric constant	1.0000684	1.00013	1.000516	–	–	–
van der Waals constant a	0.03412	0.2107	1.345	2.318	4.194	–
van der Waals constant b	0.02370	0.01709	0.03219	0.03978	0.05105	–

Phase changes and critical properties

Physical property	Helium	Neon	Argon	Krypton	Xenon	Radon
Boiling point	−268.8	−245.9	−185.8	−151.7	−106.6	−61.7
Boiling point	4.15	27.15	87.15	121.2	165.2	211.3
Melting point	−272	−248.5	−189.6	−157.4	−111.5	−71.0
Melting point	1.15	24.65	83.55	115.75	161.65	202.15
Critical temperature	5.25	44.5	150.85	209.35	289.74	378.15
Critical pressure	2.26	26.9	48.3	54.3	57.64	62
Critical density	0.0693	0.484	0.536	0.908	1.100	–
Triple point temperature	2.19	24.562	83.80	115.76	161.37	202
Triple point pressure	5.1	43.37	68.90	73.15	81.66	70

Economic data

Radon is available only in very small quantities, and due to its short half-life, is generally produced by a radium-226 source in secular equilibrium. Oganesson is almost impossible to produce and with a very short half-life, it is not readily available for purchase.