Three Students were asked to find the identity of the metal in a particular sulfate salt. They dissolved a 0.1472-g sample of the salt in water adn treated it with excess barium chloride, resulting in the precipitation of barium sulfate. After teh precipitate had been filtered and dried, it weighed 0.2327 g. Each student analyzed the data independently and came to different conclusions. The conclusions were that the metal is sodium, titanium or gallium. What further tests you suggest to determine which student is most likely correct. This is how I tried to tackle the problem. Since the precipitate is BaSO4 and weighs .2327 g, calculating the molar mass of BaSO4, the no. of moles of precipitate I get is 9.97129E-4 mol. Thus the sulfate ions are 9.97129E-4 mol. Since no. of moles of sulfate cannot change during reaction, when the sulphur is combined with the metal, then too it is in the quantity 9.97129E-4 mol which means it has mass 0.09579 g which means that mass of metal is 0.051405 g If the metal has valency 1, then no. of moles of metal is 2*9.97E-4 mol If the metal has valency 2, then no. of moles of metal is 9.97E-4 mol If the metal has valency 3, then no. of moles of metal is 9.97E-4*2/3 mol Taking each possibility into account, I get as molar mass for metal valency 1, 25.77 g/mol for metal valency 2, 51.55 g/mol for metal valency 3, 77.329 g/mol None of these molar masses correspond to any metal. Where am I going wrong?