As per electrochemical series and on the basis of electrode potential values, identify the following:
(a) gas which has highest tendency for reduction.
(b) weakest oxidising ion.
The gas which has the greatest tendency for reduction will be the most powerful oxidising agent and will possess the most positive standard reduction potential value. thus, Fluorine gas has the highest reduction potential value and will act as the most powerful oxidising agent, as its reduction potential value is 2.87 V.
The ion possessing the lowest standard reduction potential value will be the weakest oxidising agent, thus, Li+ ion will be the weakest oxidising agent, as its reduction potential value is - 3.05 V.