A redox reaction used in an introductory electrochemistry experiment is summarized by…
CHEMISTRY · Multi-part · A Level · Chemistry · Oxidation, reduction and redox reactions · Oxidation, reduction and redox reactions
Problem
A redox reaction used in an introductory electrochemistry experiment is summarized by the net ionic equation
MnO4−(aq)+5Fe2+(aq)+8H+(aq)→Mn2+(aq)+5Fe3+(aq)+4H2O(l).
Only the following aqueous reagents are available in the laboratory:
• potassium permanganate
• iron(II) sulfate
• sulfuric acid
Answer the questions that follow.
(a) Using ONLY reagents from the list, write one balanced molecular equation (with physical states) whose net ionic form is the equation given above.
(b) Show the complete ionic equation for the reaction in part (a) and verify that canceling spectator ions leads to the supplied net ionic equation.
(c) Explain why each reactant you selected exists as separate ions in solution before the reaction occurs, and justify the physical state you assigned to every product in the molecular equation.
(d) If sodium nitrate solution were inadvertently used instead of sulfuric acid to provide the acidic environment, predict whether the reaction would proceed to completion and justify your answer in terms of the reaction stoichiometry and the properties of nitrate ion.