Section 82. The Conductivity Data. 213 



gives the temperature of the measurement in degrees centigrade on 

 the hydrogen scale. The next column gives the measured conductance 

 in reciprocal ohms, multiplied by 10 and corrected for calibration and 

 lead resistance. (The letter G shows that the data were obtained in the 

 glass cell of pipette form.) 



In tables 74 and 75, the next four columns give the values of the 

 specific conductance multiplied by 10 6 . The first of the four gives the 

 uncorrected value, obtained by multiplying the measured conductance by 

 10 6 and by the conductance-capacity given in table 73 for the date next 

 preceding that of the experiment; the second gives the values obtained 

 from these by subtracting the conductance of the impurities of the water 

 given in section 79 ; and the third and fourth give the same values fur- 

 ther corrected as described in section 79 for the conductance of the 

 added base (or acid) at 18 and for the ionized water and residual hydrol- 

 ysis at the higher temperatures. The last column gives the equivalent 

 conductance, calculated by dividing the corrected specific conductance 

 by the number of equivalents per liter at t. These last were derived 

 from the milli-equivalents per kilogram as described in section 80, and are 

 given in tables 80 and 81. 



In tables 76 and 77 the sixth and seventh columns contain the specific 

 conductances, uncorrected, and corrected for the conductance of the 

 impurities in the water. The last two columns contain the correspond- 

 ing equivalent conductances. Both are given since there may be some 

 question in these cases as to the way in which the water correction should 

 be applied. 



In table 78, which contains the results with ammonium acetate, the 

 equivalent conductances are not given, since the subsequent calculations 

 are based on the specific conductances. The last column of the table 

 gives the percentage change of the specific conductance at 18, due to 

 oxidation or decomposition. The values of milli-equivalents of salt per 

 kilogram corresponding to the conductance at the higher temperature and 

 to the final conductance at 18 were obtained from the initial content by 

 changing it by a percentage amount equal to the above mentioned 

 percentage change in conductance. No similar correction was applied 

 to the acid or base content, except in the case of the experiments carried 

 to 306 with solutions containing an excess of base, in which case the 

 change in content was directly determined, as described in section 79, 

 to be that given in the table. 



