Air - Properties at Gas-Liquid Equilibrium Conditions

At standard conditions, air is a mixture of gases. However, at low temperature and high pressures the gas mixture becomes a liquid. The air phase diagram shows the phase behavior with changes in temperature and pressure. The curve between the triple point and the critical point shows the air boiling point with changes in pressure.

Critical point: The end point of the pressure-temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by the critical temperature T_c and the critical pressure P_c, phase boundaries vanish.
  Critical temperature of air:           132.63 K = -140.52 °C = -220.94 °F
  Critical pressure of air:                37.363 atm = 37.858 bar = 3.7858 MPa (MN/m²) = 549.08 psi (=lb_f/in²)

Triple point:  The temperature and pressure at which the three phases (gas, liquid, and solid) of a substance coexist in thermodynamic equilibrium
  Triple point pressure of air:         0.05196 atm = 0.05265 bar = 5265 Pa = 0.7636 psi (=lb_f/in²)
  Triple point temperature of air:    59.75 K = -213.40 °C = -352.12 °F

The figures below show the changes in thermophysical properties along the air boiling and condensation curves: Vapour pressure, density, viscosity, heat capacity, thermal conductivity.

Tabulated values given in SI and imperial units, and unit converters are given below the figures.

See also properties of Air at varying temperature and pressure: Density and specific weight at varying temperature, Density at varying pressure, Diffusion Coefficients for Gases in Air, Prandtl Number, Specific heat at varying temperature and Specific heat at varying pressure, Thermal Conductivity, Thermal Diffusivity, and Air thermophysical properties at standard conditions and Composition and molecular weight,

Phase diagram of air:


The following figures show how the properties of air changes along the boiling and condensation curves (shown in the figure above) - SI units:

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Properties of air along the boiling and condensation curves - SI units:

For full table with thermal conductivity, dynamic and kinematic viscosity - rotate the screen!

Temperature		Pressure	Density	Heat capacity CV	Heat capacity CP	Thermal conductivity		Dynamic Viscosity	Kinematic viscosity
[K]	[°C]	[bara]	[g/l], [kg/m3]	[kJ/kg K]	[kJ/kg K]	[mW/m K]	[kcal(IT)/(h m K)]	[μPa s]	[cSt], [m2/s*10-6]
Liquid
59.75	-213.40	0.05265	957.6	1.174	1.901	171.4	0.1474	376.6	0.3933
65	-208.2	0.1432	935.9	1.118	1.902	162.9	0.1401	292.4	0.3124
70	-203.2	0.31908	914.6	1.102	1.908	154.7	0.1330	234.8	0.2567
75	-198.2	0.63326	892.7	1.072	1.919	146.5	0.1260	192.4	0.2155
80	-193.2	1.1462	870.2	1.045	1.938	138.2	0.1188	160.4	0.1843
85	-188.2	1.9262	846.7	1.020	1.964	129.8	0.1116	135.8	0.1604
90	-183.2	3.0475	822.2	0.9981	2.003	121.4	0.1044	116.4	0.1415
95	-178.2	4.5886	796.2	0.9786	2.056	112.9	0.09709	100.7	0.1264
100	-173.2	6.6313	768.5	0.9617	2.130	104.4	0.08978	87.61	0.1140
105	-168.2	9.2606	738.6	0.9477	2.236	95.93	0.08249	76.41	0.1035
110	-163.2	12.564	705.6	0.9373	2.389	87.55	0.07528	66.54	0.0943
115	-158.2	16.633	668.5	0.9314	2.628	79.34	0.06822	57.57	0.0861
120	-153.2	21.557	625.3	0.9325	3.048	71.36	0.06136	49.13	0.0786
125	-148.2	27.427	571.4	0.9473	4.001	63.66	0.05474	40.76	0.0713
130	-143.2	34.295	488.4	1.010	8.846	58.05	0.04992	31.07	0.0636
132.63	-140.52	37.858	302.6					17.83	0.0589
Gas
59.75	-213.40	0.02432	0.1421	0.7183	1.009	5.294	0.004552	4.220	29.69
65	-208.2	0.07756	0.4182	0.7219	1.017	5.844	0.005025	4.606	11.01
70	-203.2	0.19431	0.9787	0.7275	1.030	6.376	0.005482	4.970	5.078
75	-198.2	0.42282	2.006	0.7354	1.050	6.920	0.005950	5.333	2.658
80	-193.2	0.82321	3.711	0.7459	1.078	7.485	0.006436	5.694	1.534
85	-188.2	1.4665	6.336	0.7589	1.116	8.082	0.006949	6.057	0.9560
90	-183.2	2.4320	10.16	0.7746	1.166	8.725	0.007502	6.427	0.6327
95	-178.2	3.8047	15.50	0.7928	1.232	9.439	0.008116	6.810	0.4393
100	-173.2	5.6742	22.77	0.8137	1.320	10.26	0.008819	7.215	0.3169
105	-168.2	8.1341	32.49	0.8375	1.440	11.24	0.009662	7.659	0.2357
110	-163.2	11.282	45.42	0.8651	1.614	12.47	0.01072	8.163	0.1797
115	-158.2	15.223	62.75	0.8981	1.887	14.15	0.01216	8.770	0.1398
120	-153.2	20.067	86.57	0.9399	2.373	16.64	0.01430	9.552	0.1103
125	-148.2	25.949	121.5	0.9981	3.474	20.97	0.01803	10.68	0.0879
130	-143.2	33.084	182.7	1.095	8.031	31.81	0.02735	12.78	0.0699
132.63	-140.52	37.858	302.6					17.83	0.0589

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Properties of air along the boiling and condensation curves - Imperial units:

For full table with thermal conductivity, dynamic and kinematic viscosity - rotate the screen!

Temperature		Pressure	Density		Heat capacity CV	Heat capacity CP	Thermal conductivity	Dynamic viscosity		Kinematic viscosity
[K]	[°F]	[psia]	[lb/ft3]	[sl/ft3]	[Btu(IT)/lb °F]	[Btu(IT)/lb °F]	[Btu(IT)/(h ft °F)]	[lbf s/ft2 *10-6]	[lbm/ft s*10-6]	[ft2/s*10-6]
Liquid
59.75	-352.12	0.76363	59.79	1.858	0.2805	0.4541	0.09905	7.866	253.1	4.233
65	-343.7	2.077	58.43	1.816	0.2671	0.4543	0.09413	6.107	196.5	3.363
70	-334.7	4.6279	57.10	1.775	0.2632	0.4557	0.08940	4.904	157.8	2.763
75	-325.7	9.1847	55.73	1.732	0.2560	0.4584	0.08464	4.017	129.3	2.319
80	-316.7	16.624	54.32	1.688	0.2495	0.4628	0.07982	3.350	107.8	1.984
85	-307.7	27.937	52.86	1.643	0.2437	0.4692	0.07499	2.836	91.24	1.726
90	-298.7	44.200	51.33	1.595	0.2384	0.4783	0.07013	2.431	78.20	1.524
95	-289.7	66.552	49.71	1.545	0.2337	0.4911	0.06524	2.103	67.65	1.361
100	-280.7	96.179	47.98	1.491	0.2297	0.5088	0.06033	1.830	58.87	1.227
105	-271.7	134.31	46.11	1.433	0.2264	0.5339	0.05543	1.596	51.35	1.114
110	-262.7	182.23	44.05	1.369	0.2239	0.5707	0.05059	1.390	44.71	1.015
115	-253.7	241.24	41.73	1.297	0.2225	0.6278	0.04584	1.202	38.69	0.927
120	-244.7	312.66	39.04	1.213	0.2227	0.7279	0.04123	1.026	33.01	0.846
125	-235.7	397.80	35.67	1.109	0.2263	0.9556	0.03678	0.8512	27.39	0.768
130	-226.7	497.41	30.49	0.9477	0.2411	2.113	0.03354	0.6490	20.88	0.685
132.63	-220.94	549.08	18.89	0.5872				0.3724	11.98	0.634
Gas
59.75	-352.12	0.3527	0.00887	0.000276	0.1716	0.2409	0.003059	0.0881	2.836	319.562
65	-342.7	1.1249	0.02611	0.000811	0.1724	0.2429	0.003377	0.0962	3.095	118.544
70	-333.7	2.8182	0.06110	0.001899	0.1738	0.2460	0.003684	0.1038	3.340	54.663
75	-324.7	6.1325	0.1253	0.003893	0.1757	0.2508	0.003998	0.1114	3.583	28.608
80	-315.7	11.940	0.2317	0.00720	0.1782	0.2574	0.004325	0.1189	3.826	16.514
85	-306.7	21.270	0.3956	0.01229	0.1813	0.2665	0.004670	0.1265	4.070	10.290
90	-297.7	35.273	0.6341	0.01971	0.1850	0.2785	0.005041	0.1342	4.319	6.811
95	-288.7	55.183	0.9677	0.03008	0.1894	0.2942	0.005454	0.1422	4.576	4.729
100	-279.7	82.297	1.421	0.04418	0.1943	0.3152	0.005926	0.0119	0.381	3.411
105	-270.7	117.98	2.028	0.06304	0.2000	0.3440	0.006493	0.1600	5.146	2.537
110	-261.7	163.63	2.836	0.08814	0.2066	0.3855	0.007207	0.1705	5.486	1.934
115	-252.7	220.79	3.917	0.1218	0.2145	0.4506	0.008173	0.1832	5.893	1.504
120	-243.7	291.05	5.405	0.1680	0.2245	0.5668	0.009612	0.1995	6.419	1.188
125	-234.7	376.36	7.583	0.2357	0.2384	0.8298	0.01212	0.2231	7.177	0.947
130	-225.7	479.84	11.41	0.3545	0.2616	1.918	0.01838	0.2668	8.584	0.753
132.63	-220.94	549.08	18.89	0.5872				0.3724	11.98	0.634

Unit converters:

Density unit converter
Dynamic viscosity unit converter
Kinematic viscosity unit converter
Pressure unit converter
Specific heat (heat capacity) and entropy unit converter 
Temperature unit converter
Thermal conductivity unit converter

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