Loss of Energy due to Chemical Union fyc. 



49 



Section K. — Effect oi Heating Aqueous Solutions of 

 the Halogens. 



Table XXIX. — Positive metal. Cadmium. 



Strength of Solution 1 equivalent weight in grains in 

 449,500 grains of water. 



Ingredients. E.M.F. 



Mixture. 



E.M.F. 



Water at 18° C. "850 Water+Cl at 10° C. 1-6508 



After heating to 90° C. during 5 minutes and cooling. 161076 

 5 „ „ 1-5650 



5 



15 „ „ 1-5078 



15 

 30 



There still remained an odour of chlorine, and the liquid 

 liberated iodine from potassium iodide after heating. The 

 loss of electromotive force was about 8' 6 per cent. 



Mixture. 



E.M.F. 



Water +Br at 9-5 C. 1-5135 



After beating to 90° C. during 5 minutes and cooling. 1 -50208 



5 „ „ 1-48492 



5 „ „ 1-4220 



15 „ „ 1-0902 



The liquid was now colourless and odourless, and showed 

 no acid reaction with test-paper. The loss of electromotive 

 force was about 34*35 per cent. The last amount of electro- 

 motive force was slightly larger than that obtained with dilute 

 hydrobrornic acid of equivalent strength. 



Mixture. 



E.M.F. 



Water+I at 10° O. M646 



After heating to 90° C. during 5 minutes and cooling. 1-14458 



55 55 55 5 ,, 55 )5 



)5 55 55 O 55 55 55 



15 



15 



The degree of colour of the liquid was diminished about 

 50 per cent. The loss of electromotive force was about 1*72 

 per cent. 



In each of these three cases a loss of electromotive force 

 Phil. Mag. S. 5. Vol. 33. No. 200. Jan. 1892. E 



