Table of specific heat capacities

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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 constant parameter is notably the volumetric heat capacity (at least for solids), which is notably 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). Paraffin, for example, 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).

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 in this table 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
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 ~ 1.25 R
Air (typical
room conditionsA)
gas 1.012 29.19 20.85 0.00121 ~ 1.25 R
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 1.50 R
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 3.13 R
Carbon dioxide CO2[4] gas 0.839B 36.94 28.46 1.14 R
Chromium solid 0.449 23.35 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 1.50 R
Gasoline (octane) liquid 2.22 228 1.64 1.05 R
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 1.50 R
Hydrogen gas 14.30 28.82 1.23 R
Hydrogen sulfide H2S[4] gas 1.015B 34.60 1.05 R
Iron solid 0.412 25.09[5] 3.537 3.02 R
Lead solid 0.129 26.4 1.44 3.18 R
Lithium solid 3.58 24.8 1.912 2.98 R
Lithium at 181 °C[6] 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 0.85 R
Methanol[7] liquid 2.14 68.62 1.38 R
Molten salt (142–540 °C)[8] liquid 1.56 2.62
Nitrogen gas 1.040 29.12 20.8 1.25 R
Neon gas 1.0301 20.7862 12.4717 1.50 R
Oxygen gas 0.918 29.38 21.0 1.26 R
Paraffin wax
C25H52
solid 2.5 (ave) 900 2.325 1.41 R
Polyethylene
(rotomolding grade)[9][10]
solid 2.3027
Silica (fused) solid 0.703 42.2 1.547 1.69 R
Silver[3] solid 0.233 24.9 2.44 2.99 R
Sodium solid 1.230 28.23 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 2.080 37.47 28.03 1.12 R
Water at 25 °C liquid 4.1813 75.327 74.53 4.1796 3.02 R
Water at 100 °C liquid 4.1813 75.327 74.53 4.2160 3.02 R
Water at −10 °C (ice)[3] solid 2.05 38.09 1.938 1.53 R
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 [11]

Mass heats capacity of building materials[]

(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 solid 0.840
Glass, crown solid 0.670
Glass, flint solid 0.503
Glass, borosilicate solid 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

See also[]

References[]

  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. ^ Jump up to: a b c d e f g "Table of Specific Heats".
  4. ^ Jump up to: a b Young; Geller (2008). Young and Geller College Physics (8th ed.). Pearson Education. ISBN 978-0-8053-9218-0.
  5. ^ Chase, M. W. (1998). "Iron". National Institute of Standards and Technology: 1–1951. Cite journal requires |journal= (help)
  6. ^ "Materials Properties Handbook, Material: Lithium" (PDF). Archived from the original (PDF) on September 5, 2006.
  7. ^ "HCV (Molar Heat Capacity (cV)) Data for Methanol". Dortmund Data Bank Software and Separation Technology.
  8. ^ "Heat Storage in Materials". The Engineering Toolbox.
  9. ^ Crawford, R. J. Rotational molding of plastics. ISBN 978-1-59124-192-8.
  10. ^ 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.
  11. ^ 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.
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