balancing of redox reaction
Answers
Explanation:
The first step to balance any redox reaction is to separate the reaction into half-reactions. The substance being reduced will have electrons as reactants, and the oxidized substance will have electrons as products. (Usually all reactions are written as reduction reactions in half-reaction tables.
Answer:
Two methods are used to balance chemical equation for redox processes: Oxidation number method and Half reaction method or Ion electron method.
(1) Oxidation number method:
Step 1 : Balance the given equation for all atoms except H and O. Identify the atoms undergoing change in oxidation number.
Step 2 : Show an increase in oxidation number for oxidised species and a decrease in oxidation number for reduced species. Balance total increase and decrease in oxidation numbers.
Step 3 : Balance O atoms by adding H_2O to the side deficient of O atoms and balance H atoms by adding H^+ ions to the side deficient of H atoms and they are finally removed by forming H_2O.
Step 4: In basic medium OH^-ions are added which are removed as H_2O.
Step 5: Check the equation with respect to number of atoms of each element on both the sides.
(2) Half reaction methods :
Step 1: Assign oxidation numbers to all atoms in the given reaction.
Step 2 : Divide the equation into two half equations, one for oxidation and the other for reduction.
Step 3: Find the loss of electrons and gain of electrons by atoms in the reaction.
Step 4: Balance the loss and gain of electrons.
Step 5: Add both the reactions.
Step 6: For acidic medium H^+ ions are added while for basic medium OH^- are added.