A sample contains palladium, cadmium, and other impurities. The mass percent of palladium and cadmium can be determined using a process that starts with the sample being dissolved in hot nitric acid. Aqueous ammonia is used to lessen the acidity of the resulting solution of Cu²⁺ and Pd²⁺ ions, and then sodium thiocyanate (NaSCN) and sulfuric acid (H₂SO₄) are added to precipitate palladium thiocyanate (PdSCN). The collected solid PdSCN is dissolved in water, treated with potassium iodate (KIO₃) to produce iodine, and then titrated with aqueous sodium thiosulfate (Na₂S₂O₃). After PdSCN is removed, the filtrate is neutralized by adding aqueous ammonia. Then, a solution of diammonium hydrogen phosphate ((NH₄)₂HPO₄) is added, resulting in a precipitate of cadmium ammonium phosphate (CdNH₄PO₄). The precipitate is transformed into cadmium pyrophosphate (Cd₂P₂O₇) by heating it to 900 °C, which is then weighed. The equations involved in the process are: 

(1) Pd(s) + NO₃^—(aq) → Pd⁴⁺(aq) + NO(g) (in acid)

(2) Pd⁴⁺(aq) + SCN^—(aq) + HSO₃^—(aq) → Pd(SCN)₂(s) + HSO₄^—(aq) (in acid)

(3) Pd²⁺(aq) + IO₃^—(aq) → Pd⁴⁺(aq) + I₂(aq) (in acid)

(4) I₂(aq) + S₂O₃^2—(aq) → I^—(aq) + S₄O₆^2—(aq) (in acid)

(5) CdNH₄PO₄(s) → Cd₂P₂O₇(s) + H₂O(g) + NH₃(g)

Give the balance equation for each reaction.