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Index of Semiconductor Process Gases - Helium

HELIUM-4

M.W. [1]

4.0026

N.B.P [2]

4.224 K

T.P

N/A

He

Pc [2]

0.2275 MPa

Tc [2]

5.2 K

Vc [3]

0.057475 m3/kmol

Note: In the tables, # is used for properties obtained from estimation methods. * and + are used to distinguish between differing data sets within a single column. If no uncertainty is specified, then no uncertainty was provided by the reference.

T

K

 $$ \frac{C_P^0(T)} {R} $$

Vapor Pressure

MPa

B(T)

cm3·
mol-1

dB/dT·T

cm3·
mol-1

C(T)

cm6·
mol-2

dC/dT·T

cm6·
mol-2

λ

mW/
(m·K)

η

µPa·s

Estimated
Uncertainty

-

-

1%

-

10%

-

0.1%

0.1%

Reference

-

-

4

4

5

5

4

4

100

2.5

-

11.636

2.114

115.30

95.88

74.8

9.6

120

2.5

-

11.944

1.288

126.64

33.54

84.4

10.8

140

2.5

-

12.096

0.692

129.07

0.37

93.4

11.9

160

2.5

-

12.157

0.242

127.78

-18.31

102.1

13.0

180

2.5

-

12.165

-0.109

124.95

-29.15

110.4

14.1

200

2.5

-

12.138

-0.390

121.52

-35.51

118.5

15.1

225

2.5

-

10.076

-0.671

117.06

-39.80

128.2

16.4

250

2.5

-

11.993

-0.896

112.75

-41.76

137.7

17.6

273.15

2.5

-

11.906

-1.066

109.01

-42.36

146.2

18.7

275

2.5

-

11.899

-1.078

108.73

-42.37

146.9

18.8

300

2.5

-

11.798

-1.229

105.04

-42.22

155.9

19.9

325

2.5

-

11.695

-1.356

101.69

-41.60

164.6

21.0

350

2.5

-

11.590

-1.464

98.63

-40.73

173.2

22.1

375

2.5

-

11.486

-1.556

95.86

-39.71

181.6

23.2

400

2.5

-

11.383

-1.636

93.33

-38.62

189.9

24.3

450

2.5

-

11.182

-1.767

88.91

-36.39

206.0

26.3

500

2.5

-

10.990

-1.868

85.19

-34.23

221.7

28.3

600

2.5

-

10.636

-2.013

79.30

-30.38

251.9

32.2

700

2.5

-

10.318

-2.108

74.87

-27.18

280.9

35.9

800

2.5

-

10.032

-2.174

71.42

-24.52

308.9

39.5

900

2.5

-

9.773

-2.219

68.66

-22.31

336.1

43.0

1000

2.5

-

9.538

-2.251

66.41

-20.45

362.6

46.4

1200

2.5

-

9.124

-2.288

62.95

-17.51

413.9

52.9

1400

2.5

-

8.769

-2.306

60.43

-15.29

463.3

59.3

1600

2.5

-

8.461

-2.310

58.50

-13.57

511.3

65.4

1800

2.5

-

8.189

-2.308

56.99

-12.19

558.1

71.4

2000

2.5

-

7.946

-2.300

55.76

-11.06

603.9

77.3

2500

2.5

-

7.436

-2.271

53.53

-8.98

714.8

91.5

3000

2.5

-

7.025

-2.236

52.03

-7.56

821.9

105.2

3500

2.5

-

6.683

-2.200

50.95

-6.52

926.0

118.6

4000

2.5

-

6.392

-2.164

50.13

-5.74

1027.8

131.6

4500

2.5

-

6.139

-2.129

49.49

-5.12

1127.8

144.4

5000

2.5

-

5.916

-2.096

48.98

-4.62

1226.3

157.1

6000

2.5

-

5.540

-2.034

48.20

-3.87

1419.6

181.8

7000

2.5

-

5.230

-1.979

47.65

-3.33

1609.3

206.2

8000

2.5

-

4.969

-1.929

47.23

-2.92

1796.3

230.2

9000

2.5

-

4.745

-1.883

46.91

-2.60

1981.2

253.9

10000

2.5

-

4.549

-1.841

46.65

-2.35

2164.6

277.4

References:

  1. IUPAC, "Atomic Weights of the Elements 1993," J. Phys. Chem. Ref. Data (1995, 24, 1561).
  2. Ho, C.Y. and Touloukian, Y.S., 1981 Properties of Nonmetallic Fluid Elements," (1981, McGraw-Hill Book Co., New York).
  3. "Selected Values of Properties of Chemical Compounds," Data Project; Thermodynamics Research Center, Texas A&M University, College Station, TX (1980).
  4. Hurly, J.J., and Moldover, M.R., "Ab Initio Values of the Thermophysical Properties of Helium as Standards, J. NIST Res. (2000, 105, 5).
  5. Hurly, J.J., Schmidt, J.W., Boyes, S.J., and Moldover, M.R., "Virial Equation of State of Helium, Xenon, and Helium-Xenon Mixtures from Speed-of-Sound and Burnett PT Measurements, Int. J. Thermophys, (1997, 18, 579).

Footnote:

# is used for properties obtained from estimation methods.
* and + are used to distinguish between differing data sets within a single column.

Created December 29, 2009, Updated December 5, 2019