Why doesn't potassium ion K+ from KMnO4 appear in the following two unbalanced equations: MnO4– + C2O42– Mn2+ + CO2
MnO4– + Fe2+ Mn2+ + Fe3+ ?
A. The presence of K+ would result in a net positive charge in the products.
B. The equations cannot be balanced if the potassium ion K+ is present.
C. KMnO4 is not added to either reaction.
D. K+ is a spectator ion and redox reactions are written as net ionic reactions.
E. None of these.
answer is d.
i already figured it myself, just wanted to share.
thanks
The correct answer is E. None of these.
In the given unbalanced equations, the potassium ion (K+) from KMnO4 does not appear in the final balanced equations because it is a spectator ion and does not participate in the redox reactions. Spectator ions are ions that are present in a solution but do not participate in the chemical reaction.
When balancing redox equations, only the species that undergo oxidation or reduction are involved in the reaction. In this case, the MnO4– ion is being reduced to Mn2+ and the Fe2+ ion is being oxidized to Fe3+. The potassium ion does not undergo any change in oxidation state and therefore does not participate in the redox reaction.
To balance redox equations, you would need to consider the changes in oxidation states and adjust the stoichiometry of the species involved until the number of electrons gained and lost are equal on each side of the equation. In this case, the KMnO4 compound itself is not added to either reaction, and only the MnO4– ion from it participates.
So, the correct answer is E. None of these.