Manchester Memoirs, Vol. Hi. (1908), No. T- 



VII. The Atomic Weight of Chlorine. 

 By E. C. Edgar, D.Sc. 



(Received and read /^amiary 14th, igp8.) 



The method used to redetermine this constant was 

 to burn pure dry chlorine, at the tip of a quartz jet, in an 

 atmosphere of pure dry hydrogen in a quartz " combustion 

 vessel " ; the hydrogen chloride formed was condensed in 

 a limb of it by liquid air. 



The weights of the gases burnt were found by sub- 

 tracting from the total amounts used the weights of 

 unburnt hydrogen and chlorine. 



Eight experiments were made. In six the hydrogen 

 chloride was distilled from the " combustion vessel " into a 

 steel bomb and weighed as a liquid. In three of these 

 the weights of the liquid were less than the weights ot 

 hydrogen and chlorine burnt ; in the other three the bomb 

 leaked. 



In the last two the hydrogen chloride was distilled 

 into an apparatus containing water and weighed as 

 aqueous hydrochloric acid. 



As the mean of eight experiments, the atomic weight 

 of chlorine calculated from the ratio 



weight of chlorine burnt 

 weight of hydrogen burnt 



is 35' 1 94 ; from the ratio 



weight of hydrogen chloride caught - weight of hydrogen burnt 

 weight of hydrogen burnt 



it is 35'i93 (atomic weight of hydrogen = i). 

 February 6th, igoS. 



