Trace concentrations of nitrate in groundwater can be quantified by its reaction with…
CHEMISTRY · Multi-part · AP · Chemistry · Chemical Reactions · Chemical Reactions
Problem
Trace concentrations of nitrate in groundwater can be quantified by its reaction with iodide ion under acidic conditions to yield nitric oxide gas, iodine, and water:
NO3−+I−⟶NO+I2
(The equation above is not balanced.)
(a) Construct balanced oxidation and reduction half-reactions for this process in acidic solution, including electrons, H+, and H2O as required.
(b) Combine the half-reactions from part (a) to give the overall balanced ionic equation. Report coefficients as the lowest whole-number ratio.
(c) Using your balanced equation, determine the number of moles of I2 produced when 0.0100 mol of NO3− is completely consumed.
(d) Explain, with reference to the law of conservation of charge, why the algebraic sum of ionic charges must be identical on both sides of any balanced redox equation.