Electrolysis of Alkali Salt- Vapours. 213 



this it was necessary to make an estimate of the amount of 

 salt passing between the electrodes when a solution of known 

 strength was being sprayed. 



The amount of salt passing through the tube was determined 

 by a modification of the method originally employed by 

 Arrhenius to determine the amount of salt supplied by a 

 sprayer to a flame. 



A solution containing 40 grams of lithium chloride per litre 

 was sprayed and the air and spray mixed with coal-gas and 

 the mixture then burnt from a brass tube so as to form a 

 Bunsen flame. A Bunsen burner was adjusted so as to give 

 another sensibly equal and similar flame which was placed 

 close beside the first. A weighed bead of fused LiCl was 

 held in the axis of the second flame on a platinum-wire loop 

 and its height in the flame adjusted till the tips of the two 

 flames appeared equally brightly coloured. 



Under these circumstances the rate of supply of salt to the 

 two flames must be nearly the same, so that the loss of weight 

 of the bead of LiCl measures the rate at which LiCl is supplied 

 by the sprayer. 



The loss of weight of the LiCl bead was found to be 

 7 milligrams in ten minutes in one experiment, and 6 milli- 

 grams in ten minutes in another experiment. This gives for 

 the number of milligrams of salt passing through the platinum 

 tube per second when a solution containing 1 gram in a litre 

 is being sprayed : — 



6 ' 5 — -2-7 v If)- 4 

 600x40 " 2 7X1 ° " 



For this amount of any salt we have found experimentally 



EC = 2-67xlO" 2 . 



Hence the amount of salt per second of electrochemical 

 equivalent unity which would correspond to a current of 

 1 ampere is 



2-7 xlO" 4 



2-67 x 10" 2 



= 1*01 x 10 -2 millioram. 



Now 1 ampere in one second liberates in electrolysis 

 l'04xl0 -2 milligram of hydrogen, so that it appears that 

 the factor of proportionality is nearly the same for salt- vapours 

 as for electrolytes. 



It is evident that these results prove that Faraday's laws 

 for the passage of electricity through liquids apply also to 



