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In thermodynamics, the specific volume of a substance is the ratio of the substance's volume to its mass. It is the reciprocal of density and an intrinsic property of matter as well. Specific volume is defined as the number of cubic meters occupied by one kilogram of a particular substance. The standard unit is the meter cubed per kilogram . : Specific volume for an ideal gas is also equal to the gas constant (R) multiplied by the temperature and then divided by the pressure. : Since and : Typically, the specific volume of a substance is expressed in terms such as , , , or . ==Applications== Specific volume is commonly applied to: * Molar volume * Volume (thermodynamics) * Partial molar volume Imagine a variable-volume, airtight chamber containing a certain number of atoms of oxygen gas. Consider the following four examples: * If the chamber is made smaller without allowing gas in or out, the density increases and the specific volume decreases. * If the chamber expands without letting gas in or out, the density decreases and the specific volume increases. * If the size of the chamber remains constant and new atoms of gas are injected, the density increases and the specific volume decreases. * If the size of the chamber remains constant and some atoms are removed, the density decreases and the specific volume increases. Specific volume is a property of materials, defined as the number of cubic meters occupied by one kilogram of a particular substance. The standard unit is the meter cubed per kilogram (m3/kg or m3·kg−1). Sometimes specific volume is expressed in terms of the number of cubic centimeters occupied by one gram of a substance. In this case, the unit is the centimeter cubed per gram (cm3/g or cm3·g−1). To convert m3/kg to cm3/g, multiply by 1000; conversely, multiply by 0.001. Specific volume is inversely proportional to density. If the density of a substance doubles, its specific volume, as expressed in the same base units, is cut in half. If the density drops to 1/10 its former value, the specific volume, as expressed in the same base units, increases by a factor of 10. The density of gases changes with even slight variations in temperature, while densities of liquid and solids, which are generally thought of as incompressible, will change very little. Specific volume is the inverse of the density of a substance; therefore, careful consideration must be taken account when dealing with situations that involve gases. Small changes in temperature will have a noticeable effect on specific volumes. The chart below is a visual representation of the relationship between specific volume and temperature. As stated above, specific volume varies noticeably with changes in temperature while the gas phase. The average density of human blood is 1060 kg/m3. The specific volume that correlates to that density is 0.00094 m3/kg. Notice that the average specific volume of blood is almost identical to that of water: 0.00100 m3/kg. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「specific volume」の詳細全文を読む スポンサード リンク
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