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.

Contents

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). Dulong–Petit limit also explains why dense substance which have very heavy atoms, such like lead, 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
IsobaricIsochoric
Air (Sea level, dry,
0 °C (273.15 K))
gas1.003529.0720.76430.001297
Air (typical
room conditionsA)
gas1.01229.1920.850.00121
Aluminium solid0.89724.22.4222.91 R
Ammonia liquid4.70080.083.2633.21 R
Animal tissue
(incl. human)
[2]
mixed 3.53.7*
Antimony solid0.20725.21.3863.03 R
Argon gas0.520320.786212.4717
Arsenic solid0.32824.61.8782.96 R
Beryllium solid1.8216.43.3671.97 R
Bismuth [3] solid0.12325.71.203.09 R
Cadmium solid0.23126.022.003.13 R
Carbon dioxide CO2 [4] gas0.839B36.9428.46
Chromium solid0.44923.353.212.81 R
Copper solid0.38524.473.452.94 R
Diamond solid0.50916.1151.7820.74 R
Ethanol liquid2.441121.925
Gasoline (octane)liquid2.222281.640
Glass [3] solid0.842.1
Gold solid0.12925.422.4923.05 R
Granite [3] solid0.7902.17
Graphite solid0.7108.531.5341.03 R
Helium gas5.193220.786212.4717
Hydrogen gas14.3028.82
Hydrogen sulfide H2S [4] gas1.015B34.60
Iron [5] solid0.44925.09 [6] 3.5373.02 R
Lead solid0.12926.41.4403.18 R
Lithium solid3.5824.81.9122.98 R
Lithium at 181 °C [7] solid(?)4.233
Lithium at 181 °C [7] liquid4.37930.332.2423.65 R
Magnesium solid1.0224.91.7732.99 R
Mercury liquid0.139527.981.8883.36 R
Methane at 2 °Cgas2.19135.69
Methanol [8] liquid2.1468.621.695
Molten salt (142–540 °C) [9] liquid1.562.62
Nitrogen gas1.04029.1220.8
Neon gas1.030120.786212.4717
Oxygen gas0.91829.3821.0
Paraffin wax
C25H52
solid2.5 (avg)9002.325
Polyethylene
(rotomolding grade) [10] [11]
solid2.30272.15
Silica (fused)solid0.70342.21.547
Silver [3] solid0.23324.92.442.99 R
Sodium solid1.23028.231.193.39 R
Steel solid0.4663.756
Tin solid0.22727.1121.6593.26 R
Titanium solid0.52326.0602.63843.13 R
Tungsten [3] solid0.13424.82.582.98 R
Uranium solid0.11627.72.2163.33 R
Water at 100 °C (steam)gas2.0336.527.51.53
Water at 25 °Cliquid4.181675.3474.554.138
Water at 100 °Cliquid4.216[ dubious ]75.9567.93.77
Water at −10 °C (ice) [3] solid2.0538.091.938
Zinc [3] solid0.38725.22.763.03 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

(Usually of interest to builders and solar )

Mass heat capacity of building materials
SubstancePhasecP
J⋅g−1⋅K−1
Asphalt solid0.920
Brick solid0.840
Concrete solid0.880
Glass, silicaliquid0.840
Glass, crownliquid0.670
Glass, flintliquid0.503
Glass, borosilicateliquid0.753
Granite solid0.790
Gypsum solid1.090
Marble, mica solid0.880
Sand solid0.835
Soil solid0.800
Water liquid4.1813
Wood solid1.7 (1.2 to 2.9)
SubstancePhasecP
J⋅g−1⋅K−1

Human body

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

Related Research Articles

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In physics and chemistry, "monatomic" is a combination of the words "mono" and "atomic", and means "single atom". It is usually applied to gases: a monatomic gas is a gas in which atoms are not bound to each other. Examples at standard conditions of temperature and pressure include all the noble gases, though all chemical elements will be monatomic in the gas phase at sufficiently high temperature. The thermodynamic behavior of a monatomic gas is much simpler when compared to polyatomic gases because it is free of any rotational or vibrational energy.

References

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  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. 1 2 3 4 5 6 7 "Table of Specific Heats".
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  9. "Heat Storage in Materials". The Engineering Toolbox.
  10. Crawford, R. J. Rotational molding of plastics. ISBN   978-1-59124-192-8.
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  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.