SUNLIGHT UPON METHYL ALCOHOL. 69 
for five and twenty-five hours respectively. Both gave tests 
for formaldehyde by the three methods, the tube heated for the 
longer time contained the larger amount. Both still contained 
formaldehyde. 
Five cubic centimeters methyl alcohol from methyl benzoate, 
first method, 5 cubic centimeters conductivity water, and 1 cubic 
centimeter hydrogen peroxide were sealed in a tube and heated 
to 100° for twenty-five hours. Strong tests for formaldehyde 
were obtained by Leach’s, Hehner’s, and Rimini’s reactions. 
Ill. THE QUESTION OF THE PRODUCTION OF HYDROGEN PEROXIDE 
BY THE ACTION OF SUNLIGHT ON WATER AND OXYGEN. 
In view of the preceding article on the oxidation of methyl 
alcohol by the action of oxygen in the sunlight or hydrogen perox- 
ide in the dark, it seems of interest to study the question of the 
formation of hydrogen peroxide by light acting on water and 
oxygen alone. If hydrogen peroxide is always produced under 
these circumstances, even in small amounts, it is not necessary 
to seek further for an explanation of the oxidation of methyl 
alcohol in the sunlight when water is present. In the absence 
of water, and the evidence seems to point to the conclusion that 
water is not necessary,*° other theoretical considerations must 
be resorted to, such as the methylene dissociation of methyl 
alcohol or the labile hydrogen atom, to explain the mechanism 
of the reaction. I believe that, when working in sealed tubes 
as I have done, ozone formation can be excluded.** 
It is well known™ that hydrogen peroxide is found in the air, in rain, 
* See work on the decomposition of methyl alcohol by light of quartz 
mercury lamp (Berthelot and Gaudechon), and the decomposition of ether 
and amyl alcohol by sunlight (A. Richardson) previously cited. 
* On this point see This Journal, Sec. A (1909), 4, 148. y 
“The references in the literature are too numerous to quote. Many 
are to be found in Eder, Photochemie. Halle a. S. (1906). Especial 
attention is called to the work of Schéne, Ber. d. deutschen chem. Ges. 
(1898), 26, 3011, and (1894), 27, 1283. Richardson, Journ. Chem. Soc. - 
London (1894), 65, 453, has noted that both oxygen and light are neces- 
sary adjuncts to the formation of hydrogen peroxide in oxalic acid solution. 
Bach, Compt. rend. Acad. sci. (1897), 124, 951, states that peroxides 
are formed by the slow oxidation by the air in the light or in the dark 
of a considerable list of substances among which may be mentioned 
phosphorus, sodium, methyl, ethyl, isopropyl alcohols, glycerol, formal- 
dehyde, glucose, oxalic acid, phenol, and benzene. 
Franz Fischer and Ringe, Ber. d. deutschen chem. Ges. (1908), 41, 945, 
review the question of the stability of hydrogen peroxide and prepare the 
compound by the union of water and oxygen under a number of different 
conditions. 
