IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Glass Ball as Bullet Solubility System: 1-Methylnaphthalene with Sodium chloride and Water
Components:
   (1) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail
   (2) Sodium chloride; NaCl; [7647-14-5]  NIST Chemistry WebBook for detail
   (3) 1-Methylnaphthalene; C11H10; [90-12-0]  NIST Chemistry WebBook for detail
Original Measurements:
   Schwarz, F.P., J. Chem. Eng. Data. 1977, 22, 273-7.

 Variables:
   Temperature = 8.1 °C - 28.5 °C   
pH = Salinity: 30 g(2)/kg sln
   Concentration = Salinity: 30 g(2)/kg sln

 Prepared By:
   W.Y. Shiu, D. Mackay

 Experimental Remarks:
   The corresponding mass percent and mole fraction, x1, at 25.0° calculated by the compiler are 2.34 × 10–3 g(1)/100 g sln and 3.06 × 10–6.

 Experimental Data:   (Notes on the Nomenclature)
  
Solubility of 1-methylnaphthalene in 0.5 mol(2)/L
t/°C104 * Concentration c1 [mol dm**-3]
8.11.23
11.11.35
15.51.49
17.41.53
18.21.54
20.71.54
23.31.63
25.01.69
28.51.81
 Method/Apparatus/Procedure:
   The solubility of 1-methylnaphthalene in NaCl solution was determined by fluorescence and UV absorption measurements. In the fluorescence method, saturated solution was prepared by adding excess amount of 1-methylnapthalene to an air-tight 1x1 cm quartz fluorescence cell containing 5 mL salt solution. The cell was rotated at 20 rpm for at least cell 72 hr in a thermostatted water bath and then its fluorescent intensity was measured at 350 and 320 nm. The Spectrofluorimeter employed a ratio-photon counting mode where 1- methylnaphthalene concentration was linearly related to the fluorescence signal. The UV method was used to obtain the absorptivity of 1-methylnaphthalene in ethanol therefore provide an absolute solubility scale for the fluorescence method.

 Source and Purity of Materials:
   (1) 1-Methylnaphthalene: purity > 99%, Sodium chloride: reagent grade, Ethanol: reagent grade, Water: distilled over a KMnO4 - NaOH solution and passed through a Sephadex column.

 Estimated Errors:
   Solubility: ± 3.6% (author)
   Temperature: ± 0.1°C (author)