Answer : The balanced redox reaction will be,
![4Ag(s)+8CN^-(aq)+O_2(g)+4H^+(aq)\rightarrow 4Ag(CN)_2^-(aq)+2H_2O(l)](https://tex.z-dn.net/?f=4Ag%28s%29%2B8CN%5E-%28aq%29%2BO_2%28g%29%2B4H%5E%2B%28aq%29%5Crightarrow%204Ag%28CN%29_2%5E-%28aq%29%2B2H_2O%28l%29)
Explanation :
The given chemical equation is,
![Ag(s)+CN^-(aq)+O_2(g)\rightarrow Ag(CN)_2^-(aq)](https://tex.z-dn.net/?f=Ag%28s%29%2BCN%5E-%28aq%29%2BO_2%28g%29%5Crightarrow%20Ag%28CN%29_2%5E-%28aq%29)
In the half reaction method, the number of atoms in each half reaction and number of electrons must be balanced.
The half reactions in the acidic medium are :
Reduction :
......(1)
Oxidation :
.......(2)
Now multiply the equation (2) by 4 and then added both equation, we get the balanced redox reaction.
Thus, the balanced redox reaction will be,
![4Ag(s)+8CN^-(aq)+O_2(g)+4H^+(aq)\rightarrow 4Ag(CN)_2^-(aq)+2H_2O(l)](https://tex.z-dn.net/?f=4Ag%28s%29%2B8CN%5E-%28aq%29%2BO_2%28g%29%2B4H%5E%2B%28aq%29%5Crightarrow%204Ag%28CN%29_2%5E-%28aq%29%2B2H_2O%28l%29)