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PLEASE HELP!! Group 2 physical and chemical properties and reaction questions!!!!?

• Currently doing AS chemistry and there is a examination style question part in my book, but i am really struggling with some questions, and there is no information to aid me in answering the questions, so if someone could please explain them to me? 1. Describe the chemical test you could perform to distinguish between separate aqueous solutions of sodium sulfate and sodium nitrate . State the observation you would make with each solution. write an equation for each reaction that occurs the first one would be the sulfate ion test, so first acidifiy the solution by adding HCL or NO-² 3, then add barium chloride and a white precipitate of barium sulfate will be formed, but for the nitrate i dont understand what reaction occurs and why?! 2.a) a small sample of barium metal was added to water in a flask. when the reaction had ceased, the contents of the flask were treated with a small amount of dilute aqeous sodium sulfate describe all that you would observe and write equations, with state symbols for the reactions that occur okay so i know this one: barium metal will react vigorously will water to produce barium hydroxide and hydrogen so Ba(s) + 2H2O(l)--> Ba(OH)2 (aq) + H2 then barium hydroxide and sodium sulfate, because the hydroxide of barium is very soluble, it reacts to produce a strongly alkaline solution of barium sulfate, which is a precipitate? b) dilute sodium hydroxide solution was added drop wise until in excess to separate dilute aqueous solutions of magnesium chloride and barium chloride describe what you would observe in each case and account for you observations Hmmm, so magnesium hydroxide would be formed, which is almost insoluble, suspension in water? and this is because group 2 hydroxides get less soluble up the group, so magnesium hydroxide is not soluble at all? and barium hydroxide would be formed, which is very soluble, because group 2 hydroxides become more soluble as you go down the group? i really don't know, my chem teacher hasn't been here for 1 week and a bit, so we had to teach ourselves okay last question describe a test to show the presence of sulfate ions in an aqueous solution, give the results of this test when performed on separate aqueous solutions of magnesium chloride and magnesium sulfate, write equations for the reactions occurring firstly make the solution acidic by adding hydrochloric acid or nitric acid, then add barium chloride to see if any sulfate ions are present, erm the reaction with magnesium sulfate would produce a white insoluble precipitate of barium sulfate, what about the chloride one?! how are we meant to know how it reacts, its not in my book?!! thank you so much to anyone who helps me!

• Answer:

  At first glance your question looked extremely long, but as I read through it dawned on me that you've already answered the essential parts corrrectly. The points you were querying , (as I interpret it) were: 1) The reaction of nitrate ion, when testing with barium chloride. - well, the nitrate ion doesn't react. It just stays floating around in solution. So does the sodium ion. They are spectator ions. But you'd be able to tell which solution was the sodium nitrate because that one didn't form a precipitate. in your notes about qn 2, you missed off the state symbol for H2 but that's trivial. I'm sure you put it on your written answer. You are spot on with the solubility of group 2 hydroxides; well done. And your last question is similar to the first point, but this time it would be the chloride that is the spectator ion, and takes no part in the reaction, and stays in solution. What the question in the book could have asked, to make it clearer, was; 'write ionic equations for any reactions that occur' That way, the things that don't react don't need an equation.