Using lime as a precipitant, the crystal lead compounds in the precipitate were Pb 5 O 8 and PbO. -lead(II) chloride precipitates lead(11) in presence of chlorides but its solubility is not that low and even if the hence obtained solution is filtered and the filtrate passed through H2S gas still the concentration of lead(II) is sufficient enough to get precipitated as lead(II) sulphide whose black colour … The resulting precipitate is lead iodide (PbI2) and is bright yellow when potassium iodide and lead nitrate solutions are mixed together. The chemistry of phosphate precipitate formation is complex because of complexes formed between phosphate and metals and between metals and other ligands in the wastewater. (a) Sodium hydroxide and ammonium hydroxide on reaction with calcium salt give a milky white precipitate Ca(OH) 2, while that of with lead salt solution it gives chalky white precipitate Pb(OH) 2. Lead(II) is precipitated by sulfate under neutral to acidic conditions. 12. To identify the cation, the color of the precipitate and its solubility in excess are noted. Side reactions of the metals with alkalinity to form hydroxide precipitates are another factor to be considered (Jenkins and Hermanowicz, 1991). Pb(NO3)2 + 2KI = PbI2 +2KNO3 Thus, the reagent bottle which gives white precipitate is NaOH and the other one should contain NH 4 OH. The precipitate is partially soluble in concentrated sulfuric acid and dilute nitric acid and highly soluble in hot sodium hydroxide or acetate buffer: Pb 2+ (aq) + SO 4 2− (aq) PbSO 4 (s) [white] PbSO 4 (s) + … Precipitate formation is useful in the detection of the type of cation in a salt. The formation of PbO was due to the dehydration of lead hydroxide and the presence of Pb 5 O 8 was attributed to the atmospheric oxidation. When soda ash was added to the lead nitrate solution the precipitate generated was mainly composed of cerussite (PbCO 3) and when sodium sulfide was … OH is so low that it cannot precipitate the hydroxide of calcium. If a little sodium hydroxide solution is added to colourless lead(II) nitrate solution, a white precipitate of lead(II) hydroxide is produced. To do this, an alkali first reacts with the unknown salt to produce a precipitate that is the hydroxide of the unknown salt.