100.0mg of basic b(4)II lead phosphate was dissolved in water. Its lead content is precipitated after a suitable reaction in the form of lead chromate.II. This precipitate in an acidic KI solution forms an amount of iodine that can discolor a solution of sodium thiosulfate with a volume of 11.22 cm3 and a concentration of 0.100mol/dm3 What is the formula of the compoun?

Pb2++CrO42=PbCrO4 PbCrO4+I+H+=Pb2++Cr3++I2 I2+S2O32=I+S4O62