Force to Latent Heat Sfc. of Electrolytes. 159 



The mean electromotive force had increased 21 per cent., 

 notwithstanding that the amount of heat absorbed was rela- 

 tively small, and that the water had nearly 24 per cent, less 

 power of exciting electromotive force than the concentrated 

 acid solution. 



Experiment 4. 



575 grains of Nitrate of Ammonium in 6G2 grains of 

 Water + Water. 



Fakr. 

 44 centim. of sat. sol. of AmN0 3 1 Temp, before mixing 60-0 

 34 „ water ( „ after „ 52-0 



Decrease 8*0 F. deg. 

 E.M.F. with Cd + Pt at 60° Fahr. 



Volts. Volts. 



Saturated sol. of AmNO., = '993 \ Ar „ ™ ^r -& -l • i *. nron 



Water ='850 f Mean KiUR b ? wei £ ht = ,953 ° 



The diluted solution = -9930 



p. cent. 



Increase -0400 =448 



When two similar couples of cadmium platinum, one being 

 in the concentrated and the other in the diluted solution, 

 were opposed to each other with the galvanometer in the 

 circuit, the one in the diluted liquid showed slightly the 

 greater electromotive force ; tins was a much more delicate 

 test. It is evident that notwithstanding the water had about 

 fourteen per cent, less power than the saturated solution of 

 exciting electromotive force, its addition to that liquid did 

 not reduce the mean amount of that property. 



In the remainder of the experiments a more sensitive ther- 

 mometer capable of measuring "01 of a Centigrade degree was 

 employed. 



Experiment 5. 



Saturated solution of Nitrate of Sodium + Water. 



c. 



500 grains NaN0 3 in 43 c.c. of water ) Temp, before mixing 15-40 

 298 c.c. of water f „ after „ 13-98 



Decrease 1 -42 C . deg. 



E.M.F. with Cd-f Pt at 18 c C. 



Volts Volts 



The saturated solution= 1-0073 | ,, PMI , , . , , 301Q 



Water = -850 ( Meau EMF - b ^' weight = -881b 



The diluted solution =1 -0044 



p.cent . 



Increase -1228 = 13-9 



