# Why does formic acid give positive Fehling's test?

$$\ce{HCOOH ->[\text{Fehling's solution}] CO2 + H2O}$$

The points discussed in a previous question do not account for the fact that formic acid also gives positive Fehling's test since it is not enolisable. Then what is the reason/mechanism for the reaction?

• I thought that the exact mechanism is not known in case of both fehlings and tollens. – user57048 Aug 23 '18 at 6:15
• Formic acid is something like an aldehyde, it has a hydrogen atom attached to a carbonyl group. – Oscar Lanzi Aug 23 '18 at 9:47
• Because Fehling's solution oxidizes enolizable aldehydes to carboxylic acids, it does not preclude all other oxidations. Draw cupric formate and move formate electrons toward copper. – user55119 Aug 23 '18 at 23:17