1: With sulfuric acid; silver nitrate in water T=110°C; 0.5 h; 2: With (NH4)2S2O8 in water 0.5 h; Heating;

(NH4)2S2O8; silver nitrate 1.) 98percent sulphuric acid, water, 80 deg C, 30 min, 2.) reflux, 30 min; Yield given. Multistep reaction. Yields of byproduct given;

potassium permanganate in water 12 h; Heating;