Search results
Results From The WOW.Com Content Network
For this reason, KF is unsuitable for solutions containing e.g. dimethyl sulfoxide. KF has a high accuracy and precision, typically within 1% of available water, e.g. 3.00% appears as 2.97–3.03%. Although KF is a destructive analysis, the sample quantity is small and is typically limited by the accuracy of weighing.
This Wikipedia page provides a comprehensive list of boiling and freezing points for various solvents.
In thermodynamics, the cryoscopic constant, K f, relates molality to freezing point depression (which is a colligative property).It is the ratio of the latter to the former:
In the above equation, T F is the normal freezing point of the pure solvent (273 K for water, for example); a liq is the activity of the solvent in the solution (water activity for aqueous solution); ΔH fus T F is the enthalpy change of fusion of the pure solvent at T F, which is 333.6 J/g for water at 273 K; ΔC fus p is the difference ...
The relative activity of a species i, denoted a i, is defined [4] [5] as: = where μ i is the (molar) chemical potential of the species i under the conditions of interest, μ o i is the (molar) chemical potential of that species under some defined set of standard conditions, R is the gas constant, T is the thermodynamic temperature and e is the exponential constant.
A formula to compute the ebullioscopic constant is: [2] = R is the ideal gas constant. M is the molar mass of the solvent. T b is boiling point of the pure solvent in kelvin. ΔH vap is the molar enthalpy of vaporization of the solvent.
Potassium fluoride is the chemical compound with the formula KF. After hydrogen fluoride , KF is the primary source of the fluoride ion for applications in manufacturing and in chemistry. It is an alkali halide salt and occurs naturally as the rare mineral carobbiite .
The change in chemical potential of a solvent when a solute is added explains why boiling point elevation takes place. The boiling point elevation is a colligative property, which means that boiling point elevation is dependent on the number of dissolved particles but not their identity.