IOWA ACADEMY OF SCIENCES, 
191 
reaction represented in equation (18) with nascent hydro- 
gen, the reaction being according to this equation: 
C2H4l2 + 4H=C2H6+2HL . . .(19). 
Here we recognize ethane, which is a saturated com- 
pound. As the hydrogen has substituted itself in place of 
the iodine, instead of merely adding itself to the compound, 
we have definite proof that the product formed by the 
reaction expressed by equation (18) is also a saturated com- 
pound, differing entirely from acetylene in its chemical 
nature and composition. 
C2H4I2 is called ethylene iodide. It is a solid melting 
at 81°. It is now treated with lead monoxide at 130° 
temperature when a chemical reaction is effected in which 
the iodine and oxygen exchange places and acetaldelyde is 
evolved. The reaction is represented by this equation: 
C2H4I2+ Pb 0=C2H40+Pb I 2 . . . .(20). 
The acetaldehyde may now be converted to ethyl alcohol 
by one of the methods previously described. 
If the lead iodide, resulting from the reaction expressed 
in equation (20), is submitted to an intense heat, the iodine 
will be liberated and may be recovered and reconverted 
into hydriodic acid. The lead will remain behind in the 
form of lead monoxide and may be used over again, the 
cost of iodine need not, therefore, be considered in these 
reactions. 
It has been found that acetylene in contact with a solu- 
tion of caustic potash and air, changes in the presence of 
diffused sunlight to acetic acid, which has the formula 
HC2H3O. The reaction is probably represented thus: 
C2H2+0+H3 0+(K0H)=(K0H)+HC2Hb02 . . . .(21). 
There would b© a reaction, however, between the potas- 
sium hydroxide and acetic acid which would result in 
potassium aectate and water, thus: 
K0H+HC2H302=KC2H302+H20. . . .(22), 
