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Conductivity or specific conductance of an electrolyte solution is a measure of its ability to conduct electricity. The SI unit of conductivity is siemens per meter (S/m). Conductivity measurements are used routinely in many industrial and environmental applications as a fast, inexpensive and reliable way of measuring the ionic content in a ...
κ is the measured conductivity (formerly known as specific conductance), [3] c is the molar concentration of the electrolyte. The SI unit of molar conductivity is siemens metres squared per mole (S m 2 mol −1). [2] However, values are often quoted in S cm 2 mol −1. [4]
Electrical conductivity of water samples is used as an indicator of how salt-free, ion-free, or impurity-free the sample is; the purer the water, the lower the conductivity (the higher the resistivity). Conductivity measurements in water are often reported as specific conductance, relative to the conductivity of pure water at 25 °C.
If is expressed in terms of molality, instead of molarity (as in the equation above and in the rest of this article), then an experimental value for of water is / / at 25 °C. It is common to use a base-10 logarithm, in which case we factor ln 10 , so A is 0.509 mol − 1 / 2 kg 1 / 2 {\displaystyle 0.509{\text{ mol}}^{-1/2}{\text{kg}}^{1/2}} .
For a substance X with a specific volume of 0.657 cm 3 /g and a substance Y with a specific volume 0.374 cm 3 /g, the density of each substance can be found by taking the inverse of the specific volume; therefore, substance X has a density of 1.522 g/cm 3 and substance Y has a density of 2.673 g/cm 3. With this information, the specific ...
where g is the local acceleration due to gravity, V is the volume of the sample and of water (the same for both), ρ sample is the density of the sample, ρ H 2 O is the density of water, W V represents a weight obtained in vacuum, is the mass of the sample and is the mass of an equal volume of water. The density of water and of the sample ...
Charge carrier density, also known as carrier concentration, denotes the number of charge carriers per volume. In SI units, it is measured in m −3. As with any density, in principle it can depend on position. However, usually carrier concentration is given as a single number, and represents the average carrier density over the whole material.
The ideal gas equation can be rearranged to give an expression for the molar volume of an ideal gas: = = Hence, for a given temperature and pressure, the molar volume is the same for all ideal gases and is based on the gas constant: R = 8.314 462 618 153 24 m 3 ⋅Pa⋅K −1 ⋅mol −1, or about 8.205 736 608 095 96 × 10 −5 m 3 ⋅atm⋅K ...