RICHARDS AND ROWE. — SPECIFIC HEATS OF LIQUIDS. 193 



typical. After it has been described in detail, the other cases will be 

 given in tabular form. The purification of the acid and the prepara- 

 tion of the solution of the proper strength was already been described. 



Although the method was similar to that employed in the case of 

 the water, it will perhaps be best to give the details of a single experi- 

 ment, before all the data are given in tabular form. 



In the case of the hydrochloric acid and in all the subsequent cases 

 the total heat capacity of the calorimetric system was 12.60 grams 

 instead of 12.24 grams as given before, on account of the use of other 

 rubber stoppers weighing 4.05 grams (instead of 3.30 grams). Be- 

 cause of the smaller specific heat of hydrochloric acid as well as its 

 greater density, about 466.5 grams of this acid were used in the 

 calorimeter, instead of 450.2 grams as in the case of water. A pre- 

 liminary series of eight experiments gave an aA'erage rise of tempera- 

 ture under these conditions (the average final temperature being 20.34) 

 of 4.231°. This corresponds to a specific heat possessed by the hydro- 

 chloric acid of 0.9635, with a probable error (computed according to 

 the method of least squares) of 0.0002. The indiA'idual results need 

 not be given, as they were only approximate, but none deviated more 

 than 0.1 percent from the mean. A single experiment taken at ran- 

 dom from the much more satisfactory final series will be recorded in 

 detail before this series is summarized. 



Data of a specimen determination of the Specific Heat of 



HCl.lOOHsO. 



Series 2B, No. 1. Jan. 17, 1910. 

 Temperature Data. 



Initial thermometer reading = 

 Total Calibration correction = — 

 Initial temperature (corrected) ( Ty) 

 Final temperature reading = 

 Total Calibration correction = — 

 Final temperature (corrected) (Z'2) 



(7^2- 7\) 



Stem exposure corr. 



Temperature interval (To-Ti) corrected = 4.233° 



Heat evolved by neutralization of acid: — 



Weight of acid = 1 14 . 87 gms. 



Q for 100.00 grams at 20.31° = 2170.7 cals.^^ 

 Q for 1 14 . 87 grams at 20 . 31° = 2493 . 4 " 



11 This value is calculated from the preceding Table II. 



