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Table of specific heat capacities

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The table of specific heat capacities gives the volumetric heat capacity as well as the specific heat capacity of some substances and engineering materials, and (when applicable) the molar heat capacity.

Generally, the most notable constant parameter is the volumetric heat capacity (at least for solids) which is around the value of 3 megajoule per cubic meter per kelvin:[1]

Note that the especially high molar values, as for paraffin, gasoline, water and ammonia, result from calculating specific heats in terms of moles of molecules. If specific heat is expressed per mole of atoms for these substances, none of the constant-volume values exceed, to any large extent, the theoretical Dulong–Petit limit of 25 J⋅mol−1⋅K−1 = 3 R per mole of atoms (see the last column of this table). For example, Paraffin has very large molecules and thus a high heat capacity per mole, but as a substance it does not have remarkable heat capacity in terms of volume, mass, or atom-mol (which is just 1.41 R per mole of atoms, or less than half of most solids, in terms of heat capacity per atom). The Dulong–Petit limit also explains why dense substances, such as lead, which have very heavy atoms, rank very low in mass heat capacity.

In the last column, major departures of solids at standard temperatures from the Dulong–Petit law value of 3 R, are usually due to low atomic weight plus high bond strength (as in diamond) causing some vibration modes to have too much energy to be available to store thermal energy at the measured temperature. For gases, departure from 3 R per mole of atoms is generally due to two factors: (1) failure of the higher quantum-energy-spaced vibration modes in gas molecules to be excited at room temperature, and (2) loss of potential energy degree of freedom for small gas molecules, simply because most of their atoms are not bonded maximally in space to other atoms, as happens in many solids.

Table of specific heat capacities at 25 °C (298 K) unless otherwise noted.[citation needed] Notable minima and maxima are shown in maroon.
Substance Phase Isobaric mass
heat capacity
cP
J⋅g−1⋅K−1
Molar heat capacity,
CP,m and CV,m
J⋅mol−1⋅K−1
Isobaric
volumetric
heat capacity

CP,v
J⋅cm−3⋅K−1
Isochoric
molar by atom
heat capacity
CV,am
mol-atom−1
Isobaric Isochoric
Air (Sea level, dry,
0 °C (273.15 K))
gas 1.0035 29.07 20.7643 0.001297
Air (typical
room conditionsA)
gas 1.012 29.19 20.85 0.00121
Aluminium solid 0.897 24.2 2.422 2.91 R
Ammonia liquid 4.700 80.08 3.263 3.21 R
Animal tissue
(incl. human)
[2]
mixed 3.5 3.7*
Antimony solid 0.207 25.2 1.386 3.03 R
Argon gas 0.5203 20.7862 12.4717
Arsenic solid 0.328 24.6 1.878 2.96 R
Beryllium solid 1.82 16.4 3.367 1.97 R
Bismuth[3] solid 0.123 25.7 1.20 3.09 R
Cadmium solid 0.231 26.02 2.00 3.13 R
Carbon dioxide CO2[4] gas 0.839B 36.94 28.46
Chromium solid 0.449 23.35 3.21 2.81 R
Copper solid 0.385 24.47 3.45 2.94 R
Diamond solid 0.5091 6.115 1.782 0.74 R
Ethanol liquid 2.44 112 1.925
Gasoline (octane) liquid 2.22 228 1.640
Glass[3] solid 0.84 2.1
Gold solid 0.129 25.42 2.492 3.05 R
Granite[3] solid 0.790 2.17
Graphite solid 0.710 8.53 1.534 1.03 R
Helium gas 5.1932 20.7862 12.4717
Hydrogen gas 14.30 28.82
Hydrogen sulfide H2S[4] gas 1.015B 34.60
Iron[5] solid 0.449 25.09[6] 3.537 3.02 R
Lead solid 0.129 26.4 1.440 3.18 R
Lithium solid 3.58 24.8 1.912 2.98 R
Lithium at 181 °C[7] solid(?) 4.233
Lithium at 181 °C[7] liquid 4.379 30.33 2.242 3.65 R
Magnesium solid 1.02 24.9 1.773 2.99 R
Mercury liquid 0.1395 27.98 1.888 3.36 R
Methane at 2 °C gas 2.191 35.69
Methanol[8] liquid 2.14 68.62 1.695
Molten salt (142–540 °C)[9] liquid 1.56 2.62
Nitrogen gas 1.040 29.12 20.8
Neon gas 1.0301 20.7862 12.4717
Oxygen gas 0.918 29.38 21.0
Paraffin wax
C25H52
solid 2.5 (avg) 900 2.325
Polyethylene
(rotomolding grade)[10][11]
solid 2.3027 2.15
Silica (fused) solid 0.703 42.2 1.547
Silver[3] solid 0.233 24.9 2.44 2.99 R
Sodium solid 1.230 28.23 1.19 3.39 R
Steel solid 0.466 3.756
Tin solid 0.227 27.112 1.659 3.26 R
Titanium solid 0.523 26.060 2.6384 3.13 R
Tungsten[3] solid 0.134 24.8 2.58 2.98 R
Uranium solid 0.116 27.7 2.216 3.33 R
Water at 100 °C (steam) gas 2.03 36.5 27.5 1.53
Water at 25 °C liquid 4.1816 75.34 74.55 4.138
Water at 100 °C liquid 4.216 [dubiousdiscuss] 75.95 67.9 3.77
Water at −10 °C (ice)[3] solid 2.05 38.09 1.938
Zinc[3] solid 0.387 25.2 2.76 3.03 R
Substance Phase Isobaric
mass
heat capacity
cP
J⋅g−1⋅K−1
Isobaric
molar
heat capacity
CP,m
J⋅mol−1⋅K−1
Isochore
molar
heat capacity
CV,m
J⋅mol−1⋅K−1
Isobaric
volumetric
heat capacity

CP,v
J⋅cm−3⋅K−1
Isochore
atom-molar
heat capacity
in units of R
CV,am
atom-mol−1

A Assuming an altitude of 194 metres above mean sea level (the worldwide median altitude of human habitation), an indoor temperature of 23 °C, a dewpoint of 9 °C (40.85% relative humidity), and 760 mmHg sea level–corrected barometric pressure (molar water vapor content = 1.16%).

B Calculated values
*Derived data by calculation. This is for water-rich tissues such as brain. The whole-body average figure for mammals is approximately 2.9 J⋅cm−3⋅K−1 [12]

Mass heat capacity of building materials

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(Usually of interest to builders and solar )

Mass heat capacity of building materials
Substance Phase cP
J⋅g−1⋅K−1
Asphalt solid 0.920
Brick solid 0.840
Concrete solid 0.880
Glass, silica liquid 0.840
Glass, crown liquid 0.670
Glass, flint liquid 0.503
Glass, borosilicate liquid 0.753
Granite solid 0.790
Gypsum solid 1.090
Marble, mica solid 0.880
Sand solid 0.835
Soil solid 0.800
Water liquid 4.1813
Wood solid 1.7 (1.2 to 2.9)
Substance Phase cP
J⋅g−1⋅K−1

Human body

[edit]

The specific heat of the human body calculated from the measured values of individual tissues is 2.98 kJ · kg−1 · °C−1. This is 17% lower than the earlier wider used one based on non measured values of 3.47 kJ · kg−1· °C−1. The contribution of the muscle to the specific heat of the body is approximately 47%, and the contribution of the fat and skin is approximately 24%. The specific heat of tissues range from ~0.7 kJ · kg−1 · °C−1 for tooth (enamel) to 4.2 kJ · kg−1 · °C−1 for eye (sclera).[13]

See also

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References

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  1. ^ Ashby, Shercliff, Cebon, Materials, Cambridge University Press, Chapter 12: Atoms in vibration: material and heat
  2. ^ Page 183 in: Cornelius, Flemming (2008). Medical biophysics (6th ed.). ISBN 978-1-4020-7110-2. (also giving a density of 1.06 kg/L)
  3. ^ a b c d e f g "Table of Specific Heats".
  4. ^ a b Young; Geller (2008). Young and Geller College Physics (8th ed.). Pearson Education. ISBN 978-0-8053-9218-0.
  5. ^ https://www.engineeringtoolbox.com/specific-heat-capacity-d_391.html
  6. ^ Chase, M. W. (1998). "Iron". National Institute of Standards and Technology: 1–1951. {{cite journal}}: Cite journal requires |journal= (help)
  7. ^ a b "Materials Properties Handbook, Material: Lithium" (PDF). Archived from the original (PDF) on September 5, 2006.
  8. ^ "HCV (Molar Heat Capacity (cV)) Data for Methanol". Dortmund Data Bank Software and Separation Technology.
  9. ^ "Heat Storage in Materials". The Engineering Toolbox.
  10. ^ Crawford, R. J. Rotational molding of plastics. ISBN 978-1-59124-192-8.
  11. ^ Gaur, Umesh; Wunderlich, Bernhard (1981). "Heat capacity and other thermodynamic properties of linear macromolecules. II. Polyethylene" (PDF). Journal of Physical and Chemical Reference Data. 10 (1): 119. Bibcode:1981JPCRD..10..119G. doi:10.1063/1.555636.
  12. ^ Faber, P.; Garby, L. (1995). "Fat content affects heat capacity: a study in mice". Acta Physiologica Scandinavica. 153 (2): 185–7. doi:10.1111/j.1748-1716.1995.tb09850.x. PMID 7778459.
  13. ^ Xu, Xiaojiang; Rioux, Timothy P.; Castellani, Michael P. (2023). "The specific heat of the human body is lower than previously believed: The journal Temperature toolbox". Temperature. 10 (2): 235–239. doi:10.1080/23328940.2022.2088034. ISSN 2332-8940. PMC 10274559. PMID 37332308.