80 Frankland and Duppa On the Acids [Feb. 16, 



regarded as a diatomic metal, a circumstance which has led us to study the 

 action of zincethyl upon ethylic leucate, with a view to the more satisfactory 

 elucidation of the above changes, which finally result in ethylic leucate. 

 Assuming the diatomicity of zinc, which can now no longer be doubted, it 

 is obvious that by the loss of one atom of ethyl, zincethyl will, like many 

 other organo-metallic bodies, pass from a condition of perfect to one of 

 partial saturation, in which it will play the part of a monatomic radical. 



That zincethyl, in being acted upon by oxygen, passes through two 

 distinct stages of change has been already indicated by one of us in de- 

 scribing the reactions of that body* ; for when a current of dry oxygen is 

 made to pass through an ethereal solution of zincethyl, dense white fumes 

 continue to fill the atmosphere of the vessel, until about one-half of the 

 total quantity of oxygen necessary for the complete oxidation of the zinc- 

 ethyl has been taken up. Then, the white fumes entirely cease, showing 

 the absence of free zincethyl, and at the same moment the liquid, which up 

 to that time had remained perfectly transparent, begins to deposit a copious 

 white precipitate, which continues to increase until the remaining half of 

 the oxygen is absorbed. If the process of oxidation be arrested when the 

 white fumes cease to be formed, the product effervesces violently when 

 mixed with water, owing to the escape of hydride of ethyl ; but when the 

 oxidation is completed, the white solid mass produced consists chiefly of 

 zincethylate, and does not in the slightest degree effervesce in contact with 

 water. The two stages of this reaction depend essentially upon the succes- 

 sive linking of the zinc with the two atoms of ethyl by means of diatomic 

 oxygen. The first stage of oxidation is expressed by the following equa- 

 tion: 



C 2 H s , p. r, \ C 2 H 5 



C 2 H 5 + ~ Zn \OC a H 5 - 

 Zincethyl. Zincethylo-ethylate. 



The zincethylo-ethylate thus formed is perfectly soluble in ether, and is 

 instantly decomposed by water according to the following equation : 

 fC 2 H 5 2H _ 7 JOH C 2 H 5 1 C 2 H 5 

 1 \OC 2 H 5 + 2U * U - Zn \OH+ H j H 

 Zincethylo-ethylate. Zinc hydrate. Alcohol. Ethylic hydride. 



Treated with dry oxygen, zincethylo-ethylate, in ethereal solution, absorbs 

 a second atom of that element, and it is this further absorption that con- 

 stitutes the second stage above referred to, resulting in the production of 

 ethylate of zinc, 



7n" / 0* ^ 5 4- f> 7n I O C 2 H 5 



1 {OC 2 H 3 + Zn 10C 2 H/ 



Wanklynf was the first clearly to point out the probable existence of 

 zincmonethyl, or rather its homologue zinc-monomethyl, indicating at the 



* Phil. Trans. 1855, p. 268. 



f Journal of Chem. Soc. 1861, p. 127. 



