Specific Volume - Applications

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.