Van Name and Maryott — Chlorination of Benzene. 155 



The first point investigated was the influence of changes in 

 the conditions upon the current yield when the above solu- 

 tions were electrolyzed between electrodes of platinum or of 

 Acheson graphite. Light was excluded from the cell by wrap- 

 ping with black paper and by other expedients. The total 

 amount of combined chlorine, exclusive of chloride, in the 

 product of each experiment was determined by analysis, and 

 the current yield calculated by taking the ratio of this weight 

 to one half the weight of chlorine equivalent to the number of 

 coulombs used. The coulometer was one of the oxy-hydrogen 

 type and had a graduated gas reservoir of one liter capacity. 

 During the electrolysis the liquid was invariably found to con- 

 tain free chlorine. Platinum electrodes were always slightly 

 attacked, and at the higher temperatures to such an extent 

 that ic was impracticable to use them. Graphite electrodes 

 were not in any case visibly affected. The principal results 

 are recorded in Table I. 



Table I. 

 Current, 0*05 to 0*15 amperes. Time, 20 to 36 hours. 



Composition 



Number Anode 



Current 



Temper- 



Current 



of 



of 



Material 



Density 



ature 





Yield 



Solution 



Exp. 





Amp/dm 2 



C 





% 



Ether, Benzene, 















equal volumes, 



1. 



Platinum 



o-io 



30° 





88 



saturated 



2. 



a 



o-io 



25° 





65 



with ZnCl 2 

















3. 



Platinum 



o-io 



27° 





70 





4. 



u 



0*05 



25° 





36 





5. 



(( 



0-50 



25° 





51 





6. 



u 



o-io 



10° 





64 



Glacial 



7. 



Graphite 



o-io 



10° 





14 



Acetic acid, 



8. 



a 



o-io 



70-80° 





50 



5 vols.; 



9. 



tc 



0-12 



28° 





32 



Benzene, 



10. 



(( 



0-80 



30° 





37 



4 vols.; 

 Lithium 



11. 

 12. 



Platinum 



o-io 

 o-io 



28° 

 30° 





41 

 51 



Chloride, 











Substi- Addi- 



3*5 grams per 











tution tion 



0/ *f 



100 cc 











p 



70 





13. 



Platinum 



o-io 



30° 



41 



6-6 





14. 



u 



o-io 



28° 



31 



5*5 





15. 



Graphite 



0-50 



30° 



31 



3-8 





16. 



a 



0-50 



10° 



22 



3-0 





17. 



a 



o-io 



40° 



38 



2-0 



