Search results
Results From The WOW.Com Content Network
Latent heat is energy released or absorbed by a body or a thermodynamic system during a constant-temperature process. Two common forms of latent heat are latent heat of fusion and latent heat of vaporization . These names describe the direction of energy flow when changing from one phase to the next: from solid to liquid, and liquid to gas.
Enthalpies of melting and boiling for pure elements versus temperatures of transition, demonstrating Trouton's rule. In thermodynamics, the enthalpy of fusion of a substance, also known as (latent) heat of fusion, is the change in its enthalpy resulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid, at constant pressure.
The specific heat capacity of a substance, usually denoted by or , is the heat capacity of a sample of the substance, divided by the mass of the sample: [10] = =, where represents the amount of heat needed to uniformly raise the temperature of the sample by a small increment .
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]
The SI unit of heat capacity is joule per kelvin (J/K). Heat capacity is an extensive property. The corresponding intensive property is the specific heat capacity, found by dividing the heat capacity of an object by its mass. Dividing the heat capacity by the amount of substance in moles yields its molar heat capacity.
The latent heat with respect to volume can also be called the 'latent energy with respect to volume'. For all of these usages of 'latent heat', a more systematic terminology uses 'latent heat capacity'. The heat capacity at constant volume is the heat required for unit increment in temperature at constant volume.
This relation was built on the reasoning that energy must be supplied to raise the temperature of the gas and for the gas to do work in a volume changing case. According to this relation, the difference between the specific heat capacities is the same as the universal gas constant. This relation is represented by the difference between Cp and Cv:
The amount of energy required for a phase change is known as latent heat. The "cooling rate" is the slope of the cooling curve at any point. Alloys have a melting point range. It solidifies as shown in the figure above. First, the molten alloy reaches to liquidus temperature and then freezing range starts.