Page:Scientific Papers of Josiah Willard Gibbs.djvu/427

Table V.—Acetic Acid.
Experiments of Naumann.

			Temperature
			78°		100°		110°		120°		130°		140°		150°		160°		185°
A $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.				393.5		411		432		455		477		498.5				565
	D. calc.				3.39		3.23		3.06		2.90		2.75		2.61				2.28
	D. Obs.				3.44		3.31		3.14		2.97		2.82		2.68				2.36
	Exc. of D. obs.				+.05		+.08		+.08		+.07		+.07		+.07				+.08
B $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.		342.3	359.3	377.5	398.5	417.5	436.5		495
	D. calc.		3.35	3.18	3.02	2.85	2.70	2.57		2.26
	D. Obs.		3.37	3.22	3.06	2.89	2.75	2.63		2.31
	Exc. of D. obs.		+.02	+.04	+.04	+.04	+.05	+.06		+.05
C $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.		258							382
	D. calc.		3.26							2.22
	D. Obs.		3.17							2.25
	Exc. of D. obs.		-.09							+.03
D $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.		232		252	274	287.5	300		335
	D. calc.		3.23		2.87	2.72	2.58	2.46		2.21
	D. Obs.		3.12		2.94	2.68	2.54	2.44		2.23
	Exc. of D. obs.		-.11		+.07	-.04	-.05	-.02		+.02
E $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.	164	186	197	209	221	232	243	253	269
	D. calc.	3.53	3.15	2.97	2.81	2.65	2.52	2.41	2.32	2.18
	D. Obs.	3.41	3.06	2.91	2.75	2.61	2.50	2.40	2.31	2.22
	Exc. of D. obs.	-.12	-.09	-.06	-.06	-.04	-.02	-.01	-.01	+.04
F $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.	149	168			201
	D. calc.	3.50	3.12			2.62
	D. Obs.	3.34	3.01			2.56
	Exc. of D. obs.	-.16	-.11			-.06
G $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.	137	156	166.5	180	188	199	208.2		230
	D. calc.	3.48	3.09	2.92	2.75	2.60	2.47	2.37		2.17
	D. Obs.	3.26	2.98	2.81	2.61	2.50	2.40	2.29		2.14
	Exc. of D. obs.	-.22	-.11	-.11	-.14	-.10	-.07	-.08		-.03
H $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.	113	130	138.5	149	157.5	168.2	175		191.5
	D. calc.	3.42	3.03	2.85	2.69	2.55	2.43	2.33		2.15
	D. Obs.	3.25	2.94	2.78	2.60	2.47	2.32	2.26		2.13
	Exc. of D. obs.	-.17	-.09	-.07	-.09	-.08	-.11	-.07		-.02
J $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.	80	92	98.5	106	112.5	117.3		129.2
	D. calc.	3.32	2.91	2.73	2.58	2.45	2.35		2.21
	D. Obs.	3.06	2.76	2.61	2.46	2.34	2.27		2.11
	Exc. of D. obs.	-.26	-.15	-.12	-.12	-.11	-.08		-.10
K $\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \ \end{matrix}}\right.}$	Pressure.	66	77.7	84	89.5	93	98	103		110.5
	D. calc.	3.26	2.85	2.68	2.53	2.40	2.31	2.24		2.12
	D. Obs.	3.04	2.66	2.49	2.37	2.32	2.24	2.16		2.11
	Exc. of D. obs.	-.22	-.19	-.19	-.16	-.08	-.07	-.08		-.01

in order the pressure of an experiment, the density calculated by equation (12), the observed density, and the excess of observed density, the temperature of the experiment being given at the head of the column. These experiments, taken by themselves, seem to show an effect of pressure upon the density about one third greater than is indicated by the formula. But the divergences (of which the greatest is .26 and the average .085) are not large in view of the fact that the experiments were undertaken rather with the desire of obtaining a great number of observations with moderate labor, than with the intention of attaining the greatest possible accuracy.