Specific Heats of Gases

Specific heat is the heat needed to increase the unit weight of material via Btu/lb F (British thermal units per pound degree Fahrenheit). Specific heats of gases are needed to create connections between temperature and enthalpy of gas. Because most of materials fluctuate in pressure and volume together with variance in temperature, the specific heat of gases could be on possibly constant pressure or on constant volume.

In both solids and liquids there may be minimal variation if they're cooled or heated; on the contrary, the volume and pressure of gases can change and sizable. For that reason, there isn't any distinction in specific heats intended for liquids and solids and, in contrast to for the specific heats of gases are various on consistent volume Cv or on consistent pressure Cp.

Consistent pressure Cp is usually greater as compared to consistent volume Cv through the quantity of heat needed to perform expansion. Figure 1 shows the values of Consistent pressure Cp at consistent atmospheric pressure pertaining to a variety of steam and gases. Immediate values will probably be various from these. Pertaining to k value of diatomic gases in which k=Cp/Cv, is definitely 1.4, and k value of monatomic gases is 1.66.
Figure 1: Specific Heats of Gases Diagram
(Source: Book-Boiler for Power and Process-Kumar Rayaprolu)

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