The completely balanced reaction of the half-reaction in acidic solution is ; MnO₄⁻ (aq) + 3e⁻ + 4H⁺ ------> MnO₂(s) + 2H₂O(l)
Given data :
The half-reaction in acidic solution
MnO₄⁻ (aq) --> MnO₂(s)
Determine the oxidation number on both sides
Oxidation number of Mn in MnO₄⁻ = +7
Oxidation number of Mn in MnO₂ = +4
First step : Balance the oxidation number
MnO₄⁻ (aq) + 3e⁻ ------ > MnO₂(s)
Next step : Balance the charge in the reaction
MnO₄⁻ (aq) + 3e⁻ + 4H⁺ ------> MnO₂(s)
Final step : Completely balance the half reaction
MnO₄⁻ (aq) + 3e⁻ + 4H⁺ ------> MnO₂(s) + 2H₂O(l)
Hence we can conclude that The completely balanced reaction is :
MnO₄⁻ (aq) + 3e⁻ + 4H⁺ ------> MnO₂(s) + 2H₂O(l)
Learn more about Balancing half-reaction : https://brainly.com/question/26263317
