THE CHEMICAL L.\BOKATORY OF THE I'. S . DEPARTMENT O F AGRICLLTUKE, S E S T 11V H. 11'. 11'1LZY.--NO. IO.]
[CONTRIBUTIONSFROM
CONTRACTION OF AQUEOUS SOLUTIONS OF ACETONE. R Y K . T. I' >IC E~xciv.
I
N the following determinations, mixtures of known weights of
acetone aiict water \yere niaile, the specific gravity tletermined by a piktionieter and froni this figure the volume calculatecl. T h e acetone used was bought from a New I'ork firm and was of good purity, being free from methyl alcohol. I t was fractionated and the fraction retained was boiled over calciuin chlorid under a reflux coiidenser for three days. This porticin was orice more fractionated. The portion finally used boiled at 56.4" ( a i r ) . Other samples were prepared for comparison by distilling acetates and by purifying the S e w York article by iiieaiis of the sulphite compound. These various preparations possessed esseiitially tlie same boiling points and specific gra\.it>-. 111 detail tlie iiietliod eiiip1oyt.d was to weigh a flask, add water, weigh, add acetolie. reweigh. iiiix tlie uiiited fluids 1)shaking and fitiallj- tleterniiiie the specific gravity, first at 2 0 7 and then without refilling the pikiioilieter, at 2 j". The figures thus obtained are given i n tlie aiineseti table : I
