A Manual of the Chemistry of the Carbon Compounds

TEE CARBON COMPOUNDS. 183
oxidation ia converted into oxalic acid. The second acid of the series,
malouic acid, is formed by oxidizing ethene-lactic acid, which hns
to be regarded as the first oxidation-product of primary propene glycol.
All acids of this series with the exception of oxalic acid contain
an define combined with two carboxyla This is shown uot only
by the different modes of formation of these acids, but also by many
of their decompositions.
When ethene bibromide is heated with potassium cyanide the
nitrile of succinic acid is formed, aud this compound, by the action
of caustic potash, yields the latter acid :—
CN CO.OH
VJOt + 4^0 = VtM4
ON CO.OH
When a galvanic current is passed through a solution of potassium
succinate, the acid is decomposed into ethene, carbon dioxide and
hydrogen:—
CO.OH
CO.OH
l'he chlorine in ohloracetic acid may be replaced by cyanogen,
aud tlms cyanaeetit add is formed, a compound being a monobasic
acid as well as a nitrile, and yielding inalonic acid by the action
of alkalis :•—
CN CO.OH
CH2 + 2H2O = CH2 + NH3
CO.OH CO.OH
a Cyanopropionic acid is converted by the same reaction into
isosuceinic acid :—
CHS
CHS
0H--CN + 2H2O = CH—CO.OH + NH3
CO.OH CO.OH
By heating, a iodoproyionic acid with finely divided silver 1 adipk
•icid is formed:—
' 1'lic finely divided silver, or si!eer-dust, which is employed for many similar
synthetical reactions, is prepared by precipitating a cold tliluti* solution with liydiui-liloric
ncid, aud reducing tlio silver elilonde witli zinc, 'flic product is washed with
ililnto hydrochloric acid aud wntor, and dried at a gcntlo heat. It forms a very fine
dark powder, without motalUc lustro.