As part of a soil analysis on a plot of land, you want to
determine the ammonium content using gravimetric analysis with
sodium tetraphenylborate, Na B(C6H5)4–. Unfortunately, the amount
of potassium, which also precipitates with sodium
tetraphenylborate, is non-negligible, and must be accounted for in
the analysis. Assume that all potassium in the soil is present as
K2CO3, and all ammonium is present as NH4Cl. A 4.935-g soil sample
was dissolved to give 0.500 L of solution. A 150.0-mL aliquot...