The Alkaline Earths and the Halogens-Two Families in the Periodic Table

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Experimental Procedure
I. Relative Solubilities of Some Salts of the Alkaline Earths 1.To each of four small test tubes add about 1 mL (about 12 drops) of 1 M Na2SO4. 2.Then add 1 mL of 0.1 M solutions of the nitrate salts of barium, calcium, magnesium, and strontium to those test tubes, one solution to a tube. 3.Stir each mixture using a stirring rod. The stirring rod should be rinsed in a beaker of deionized water between uses. 4.Record results in the data table, noting whether a precipitate forms, and any characteristics—as color, odor, amount, size of particles, and settling tendencies—that might distinguish it. 5.Rinse test tubes and add to each I mL of 1 M Na2CO3.

6.Then add 1 mL of the solutions of the alkaline earth salts, one solution per test tube, as before. 7.Record observations.
8.Rinse test tubes, and test for solubilities of the oxalates of these cations, using 0.25 M (NH4)2C2O4 as the precipitating reagent. 9.Finally, determine the relative solubilities of the iodates of the alkaline earths, using 1 mL 0.1 M KIO3 as the test reagent. II. Relative Oxidizing Powers of the Halogen

1.Place a few milliliters of bromine-saturated water to a small text tube and add 1 mL of hexane. 2.Stopper the test tube and shake until the bromine color is mostly in the HEX layer. 3.Repeat using chlorine water and iodine water with separate samples of HEX, noting any color changes as the bromine, chlorine, and iodine are extracted from the water layer into the HEX layer. 4.Add 1 mL bromide water to three small test tubes and 1 mL HEX. 5.Then add 1 mL 0.1 M NaCl to the first test tube, 1 mL 0.1 M NaBr to the second, and 1 mL 0.1 M NaI to the third. 6.Stopper each test tube and shake, noting the color of the HEX phase above each solution. 7.Rinse the tubes and add 1 mL chlorine water and 1mL HEX to each test tube. 8.Then add 1 mL 0.1 M solutions of the sodium halide salts, one per test tube. 9.Stopper each test tube and shake, noting the...
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