Michael Thomas Flanagan's Java Scientific Library Saline Class:     Some Physical Properties of Aqueous Sodium Chloride Solutions

Last update: 5 May 2004
Main Page of Michael Thomas Flanagan's Java Library

This class contains the methods for returning the following physical properties of aqueous solutions of sodium chloride:

• Density as a function of concentration.
• Viscosity as a function of concentration and temperature.
• Refractive Index as a function of wavelength, temperature and concentration.
• Mole Fraction of NaCl in an aqueous NaCl solution.
• Molecular Weight of NaCl.
• and methods for Molar - grams per litre interconversions

import directive: import flanagan.physprop.Saline;

• Summary table of methods
• Details of methods
• Java source file (Last update: 5 May 2004)
• Other classes, in this library, used by this class
• Main Page of Michael Thomas Flanagan's Java Library

SUMMARY OF METHODS

Density	public static double density(double concentration)
Viscosity	public static double viscosity(double concentration, double temperature)
Refractive Index	public static double refractIndex(double concentration, double wavelength, double temperature)
Mole Fraction	public static double moleFraction(double concentration)
Molecular Weight	public static double MOLWEIGHT
Concentration conversions	public static double molarToGperl(double molar)
	public static double gperlToMolar(double gperl)

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METHODS

DENSITY
public static double density(double concentration)
Usage:                      double dens = Saline.density(concentration);
Returns the density (kg per cubic metre) of aqueous solutions of NaCl at the given Molar concentration and at a temperature of 20 C. The method uses a natural cubic spline interpolation on data taken from the CRC Handbook of Chemistry and Physics 56th edition. The concentration range is 0 to 5.326 M.

VISCOSITY
public static double viscosity(double concentration, double temperature)
Usage:                      double visc = Saline.viscosity(concentration, temperature);
Returns the viscosity (Pa s) of an aqueous solution of NaCl at the given Molar concentration and at the given temperature (Celsius). The method uses a natural cubic spline interpolation on data taken from the CRC Handbook of Chemistry and Physics (56th edition) for a temperature of 20 C. If the temperature is not 20 C a new value is calculated assuming that the activation energy related to viscosity is the same as that of water. Thus the value returned for temperatures other than 20 C will be an approximation that is good only at low NaCl concentrations and temperatures close to 20 C. The concentration range is 0 to 5.326 M. The temperature range is 0 to 100 degrees Celsius.

REFRACTIVE INDEX
public static double refractIndex(double concentration, double wavelength, double temperature)
Usage:                      refind = Water.refractIndex(wavelength, temperature);
Returns the refractive index of aqueous solutions of NaCl at the given wavelength (metre), given temperature (Celsius) and given Molar concentration. The method uses a natural cubic spline interpolation on data taken from the CRC Handbook of Chemistry and Physics (56th edition), a refractive increment for the added NaCl. to obtain the refractive index of water at 20 C, the salt NaCl solution at 20 C and water at the given temperature. It uses the first two to calculate, via the Lorenz-Lorentz (LL) equation, a refractive increment for the added NaCl. It then corrects this LL-increment, for temperarure, using a cubic spline interpolation on solid NaCl data. The corrected LL-increment is added to a LL transform of the refractive index of water at the given temperature and the solution refractive index is calculted from the back LL transform. The temperature range is 0 to 100 degrees Celsius. The wavelength range is 404.6 nm to 706.52 nm. The concentration range is 0 to 5.327 M. This method calls the corresponding method in the RefrIndex Class.

MOLE FRACTION
public static double moleFraction(double concentration)
Usage:                      double mf = Saline.moleFraction(molar);
Returns the mole fraction, at a temperature of 20 C, of NaCl in a aqueous NaCl solution of given molar concentration.

CONCENTRATION CONVERSION - MOLAR TO g/l
public static double molarToGperl(double molar)
Usage:                      double gperl = Saline.molarToGperl(molar);

CONCENTRATION CONVERSION - g/l TO MOLAR
public static double molarToGperl(double molar)
Usage:                      double molar = Saline.gperlToMolar(gperl);

MOLECULAR WEIGHT
public static final double MOLWEIGHT = 58.45;
Usage:                      double mw = Saline.MOLWEIGHT;
Returns the molecular weight of sodium chloride (NaCl).

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OTHER CLASSES USED BY THIS CLASS

This class uses the following classes in this library:

• CubicSpline

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This page was prepared by Dr Michael Thomas Flanagan

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