In Tollen's test for aldehyde, the overall number of electron(s) transferred to the Tollen's reagent formula [Ag(NH$$_3$$)$$_2$$]$$^+$$ per aldehyde group to form silver mirror is ___. (Round off to the Nearest integer)

In the Tollens' test, the silver ion in the Tollens' reagent $$[\text{Ag}(\text{NH}_3)_2]^+$$ is reduced from $$\text{Ag}^+$$ to $$\text{Ag}^0$$ (metallic silver that forms the silver mirror). Each silver ion gains one electron: $$\text{Ag}^+ + e^- \to \text{Ag}$$.

The overall balanced reaction is: $$\text{RCHO} + 2[\text{Ag}(\text{NH}_3)_2]^+ + 2\text{OH}^- \to \text{RCOO}^- + 2\text{Ag} + 4\text{NH}_3 + \text{H}_2\text{O}$$. The aldehyde carbon goes from oxidation state +1 (in $$\text{RCHO}$$) to +3 (in $$\text{RCOO}^-$$), losing 2 electrons overall. These 2 electrons are transferred to two $$[\text{Ag}(\text{NH}_3)_2]^+$$ ions (one electron each), producing 2 atoms of silver.

The total number of electrons transferred to the Tollens' reagent per aldehyde group is $$2$$.