Goals The primary goal of this experiment was to identify an unknown compound by running various tests to determine the qualitative solubility, conductivity, and pH value of the compound. Tests were also performed for the presence of specific cations and anions in the compound. The second goal was to discover the reactivity of the unknown compound by reacting it with different types of substances. The third goal of this project was to calculate the quantitative solubility of the unknown compound in water. The last goal was to determine the percent yield of a product formed during a reaction with the unknown compound. Experimental Design The first day of lab consisted of various preliminary tests that helped identify the unknown compound. …show more content…
To test for the presence of the ammonia cation, a scoop of the unknown compound was mixed with NaOH to see if the resulting solution had a noticeable smell that would affirm the presence of ammonia. A moist piece of pH paper was then held near the solution to see if the ammonium would dissolve the water on the pH paper. The next cation test performed was the flame test. A gram of the unknown compound was held by a metal stick above the flame of a Bunsen burner to see what color flame the compound would produce. The chart in the lab manual on page 63 was used to determine what cation correlated with what flame color. The anion tests followed the cation tests. To test for the presence of the chloride (Cl-) anion, a small scoop of the unknown compound was mixed with 1 mL of water in a test tube to create a solution. Then, 1 mL of 6 M nitric acid (HNO3) and 1 mL of silver nitrate (Ag(NO3)2) solution were added to the test tube to see if a white precipitate formed. To test for the presence of the sulfate (SO42-) anion, a small scoop of the unknown compound was mixed with 1 mL of water in a test tube to create a solution. Then, 1 mL of 6 M hydrochloric acid (HCl) and 1 mL of barium chloride (BaCl2) solution were added to the test tube to see if a white precipitate formed. To test for the presence of the carbonate (CO32-) anion, a small scoop of the unknown compound was mixed with …show more content…
The unknown compound was first reacted with an acid. To begin, 0.50 grams of KCl was mixed with 5 mL of water. Then, 1 mL of 6 M H2SO4 was added to the solution. Secondly, the unknown compound was reacted with a base. Exactly 0.50 grams of KCl was mixed with 5 mL of water, and 1 mL of 1 M NaOH was added to the solution next. Lastly, the unknown compound was reacted with two different salts. For the first salt, 0.50 grams of KCl was mixed with 5 mL of water in one beaker while 0.5 grams of NaNO3 was mixed with 5 mL of water in a different beaker. Then, the NaNO3 solution was added to the KCl solution. To perform the reaction with the second salt, 0.50 grams of KCl was mixed with 5 mL of water and 1 mL of 1 M Ag(NO3)2 was added. After performing each reaction, the solution was observed to see if a reaction occurred and the pH value of the resulting solution was tested using a pH