Densities of liquid‐acetone‐water solutions up to their normal boiling points

The densities of acetone‐water liquid solutions have been measured over the entire composition range from 20°C. to within 3° to 7°C. of the normal boiling point of the mixture. The density was measured with a Robertson pycnometer ( 13 ), which was modified slightly. The density values are thought to be accurate to within ±0.00005 density units. The technique for determining density values of the volatile mixture near the boiling temperature is given in some detail. The refractive index ( n D 25 ) of pure acetone has been redetermined and equals 1.35596 ± 0.00003.