﻿Manchester Memoirs, Vol. xlix. (1905), No. V*\. 



XIII. Note on Chlorine. 

 By D. L. Chapman, M.A., 



ANH 



C. H. Burgess, M.Sc. 



Received March 21st. Read April 18th, /<?oj. 



The effect of certain impurities in retarding or pre- 

 venting the combination of chlorine with hydrogen has 

 been investigated in greater detail by the authors. After 

 the discovery that ammonia is the main cause of what 

 has been appropriately termed by Bunsen and Roscoe 

 the ' induction period,' it was thought that other impurities 

 which can react with chlorine in light might have the 

 same effect. As far as we can judge this is not the case 

 with ether, alcohol, and benzene. The experiments upon 

 which this conclusion is based were performed in the 

 following way. Two similar actinometers were filled with 

 a mixture of hydrogen and chlorine in equal volumes. 

 To one actinometer 5 c.c. of the so-called ammonia-free 

 water were added, whilst into the other 5 c.c. of the same 

 water containing a small quantity of the impurity whose 

 influence it was desired to investigate were introduced. 

 The two actinometers were symmetrically placed with 

 respect to the standard light, and the movements of the 

 index recorded. The induction periods were small, and 

 the observed differences when alcohol, ether, and benzene 

 were used so insignificant that we are forced to conclude 

 that these substances will not prevent the action between, 

 hydrogen and chlorine. 



As we have already stated in a previous communica- 



May 27th) iqoj. 



