EXCESS VOLUMES OF (HEXADECANE PLUS PROPANONE) AT THE TEMPERATURES T=299.15K AND T=305.15K AND ORTHOBARIC DENSITIES OF PROPANONE FROM T=288.15K TO T=323.15K

The excess volumes of (hexadecane + propanone) have been measured by d ilution dilatometry at the temperatures T = 299.15 K and 305.15 K clos e to the directly determined upper critical solution temperatures T-UC S = 398.492 K. The isotherm closer to T-UCS displays the characteristi cally flat portion close to the critical mixture of volume fraction ph i = (0.4821 +/- 0.0003) of hexadecane. The orthobaric density of caref ully dried and purified propanone has been determined in a capillary p yknometer from T = 288.15 K to 323.12 K with results about 0.001 g . c m(-1) lower than older values but in good agreement with a more recent determination in which care was also taken to reduce the water conten t. The densities of (hexadecane + propanone) of known composition were determined pyknometrically at six temperatures from T = 294 K to 323 K: the results agree well with those calculated from our measured exce ss volumes, propanone densities, and dependable literature values of h exadecane density. (C) 1996 Academic Press Limited