ASTM D1481 Density and Relative Density (Specific Gravity) of Viscous Materials
ASTM D1481 Standard Test Method for Density and Relative Density (Specific Gravity) of Viscous Materials by Lipkin Bicapillary Pycnometer
6. Apparatus
6.1 Pycnometer - A side-arm type of pycnometer conforming to the dimensions given in Fig. 1 and made of borosilicate glass. The weight shall not exceed 35 g without the side arm.
6.2 Rack - A rack to use in filling the pycnometer (see Fig.2).
6.3 Constant-Temperature Oven - An oven for use in filling the pycnometer. Any oven capable of holding the filling rack, and of maintaining a temperature of approximately 100°C, can be used.
6.4 Constant-Temperature Bath - A mixture of water and glycerin, or oil bath having a depth of at least 305 mm (12 in.) and provided with heating, stirring, and thermostating devices adequate to maintain desired temperatures in the range from 20 to 100°C with an accuracy of +/-0.01°C.
6.5 Bath Thermometers - Thermometers graduated in 0.1°C subdivisions and standardized for the range of use to the nearest 0.01°C (ASTM Saybolt Viscosity Thermometers 17C to 22C are recommended). For most hydrocarbons, the density coefficient is about 0.0008 units/°C, and therefore a temperature error of +/-0.013°C would cause an error of +/-0.000 01 in density.
6.6 Pycnometer Holder - A holder, as shown in Fig. 3, is recommended for supporting the pycnometer in the bath. A single clamp device may be used.
6.7 Balance - A balance able to reproduce weighings within 0.1 mg when carrying a load of 35 g or less on each pan. The balance shall be located in a room shielded from drafts and fumes and in which the temperature changes between related weighings (empty and filled pycnometer) do not cause a significant change in the ratio of the balance arms. Otherwise, weighings shall be made by the substitution method in which the calibrated weights and pycnometer are alternatively weighed on the same balance pan. The same balance shall be used for all related weighings.
6.8 Weights - Weights shall be used whose relative values are known to the nearest 0.05 mg or better. The same set of weights shall be used for the calibration of the pycnometer and the determination of the densities, or the sets of weights shall be calibrated relative to each other.
7. Reagents and Materials
7.1 Acetone - (Warning - Extremely flammable. Use adequate ventilation.)
7.2 Isopentane - (Warning - Extremely flammable. Avoid buildup of vapors and remove all sources of ignition, especially nonexplosion-proof electrical apparatus.)
7.3 Chromic Acid (Potassium Dichromate/Conc. Sulfuric Acid) - (Warning - Causes severe burns. A recognized carcinogen. Do not get in eyes, on skin or clothing.)
7.4 Xylenes - (Warning - Flammable liquid. Aspiration hazard. May irritate skin, eyes, respiratory tract or digestive tract, or both. May cause central nervous system depression, liver and kidney damage, or exhibit reproductive and fetal effects, or both.)
