(a) The aqueous solubility of zinc hydroxide is 0.00042 grams per 1000 ml solution at 25 C. Find the Ksp of zinc hydroxide at 25 C. (b) In a gravimetric analysis, the content of iron in a carbonate sample is analyzed based on the following chemical reactions. FeCO3+2NaOH 4Fe(OH)2+O2 Fe(OH)2+Na2CO3 2Fe2O3+4H20 If the mass of iron carbonate and the final iron (III) oxide formed is 1.2 g and 0.35 g, respectively, calculate the wt% of Fe contained in the carbonate sample. (c) The pH of a 0.15 M monovalent organic acid is 4.5, calculate its pK, value