When balancing aqueous redox reactions, charge is balanced using ____

Solution: Here, we are going to fill in the blank.

Step1:

Redox reactions are the reactions in which oxidation(loss of electrons) and reduction(gain of electrons) occurs simultaneously. While balancing the redox reaction, several steps are followed:

Suppose we are to balance the equation showing the oxidation of Fe2+ ions to Fe3+ ions by dichromate ions (Cr2O7)2– in acidic medium, wherein, (Cr2O7)2– ions are reduced to Cr3+ ions. The following steps are involved in this task.

•  Produce unbalanced equation for the reaction in ionic form :

 Fe2+(aq) + (Cr2O7)2– (aq) → Fe3+ (aq) + Cr3+(aq)

• Separate the equation into half reactions:

 Oxidation half : Fe2+ (aq) → Fe3+(aq)

        Reduction half : (Cr2O7