Partner: Judy 6 October An Activity Series

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Shavonne Wilkinson
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1 Partner: Judy 6 October 2011 An Activity Series Purpose: The purpose of this lab is to verify the activity series of five metals and three halogens. This can be done by reacting the metal with various metal solutions to see which of them creates a displacement reaction. As for the halogens, it can be done in a similar way as metal, but with the halogens in their liquid form and ion form. The significance of this experiment is that geologist could use them to extract minerals from ores. Hypothesis: The hypothesis of this experiment is that the experiment will help verify the activity series of metals and halogens. This is because the reaction would not occur if the substance trying to replace the other substance is less reactive than that other substance. If the reaction did happen, there would be an apparent change in the sample. For example, if one metal was replaced by the other, the solid in the solution would be changed to the metal that was replaced. As for halogens, each halogen possess different color from another and so if one halogen was replaced by the other, the color of the solution would be changed. Materials: Part 1 Materials Quantity 6 6 mm Copper foil (Cu) 4 mm M Copper (ll) nitrate (Cu(NO 3 ) 2 ) 4mL 6 6 mm Lead foil (Pb) 4 mm M Lead nitrate (Pb(NO 3 ) 2 ) 4mL 6 mm Magnesium ribbon (Mg) 4 mm M Magnesium nitrate (Mg(NO 3 ) 2 ) 4mL 0.1 M Silver nitrate (AgNO 3 ) 4mL 6 6 mm Zinc foil (Zn) 4 mm M Zinc nitrate (ZnNO 3 ) 4mL 5mL Beral-type pipette 5 pipettes mm test tube 24 test tubes Labeling tape 30 labels Part 2 Materials Bromine water (Br 2 ) Chlorine water (Cl 2 ) Iodine water (I 2 ) Mineral oil 0.1 M Potassium iodide solution (KI) 5mL 0.1 M Sodium bromide (NaBr) 5mL Quantity 3mL 3mL 3mL 36mL 0.1 M Sodium chloride (NaCl) 5mL Labeling tape 1 roll

13 100mm test tube 18 test tubes Test tube rack 2 racks Pipette 1 pipette Dropper 6 droppers Size 2 rubber stopper 18 stoppers Procedures: Part 1. Determine an Activity Series for Metals 1.

2 13 100mm test tube 18 test tubes Test tube rack 2 racks Pipette 1 pipette Dropper 6 droppers Size 2 rubber stopper 18 stoppers Procedures: Part 1. Determine an Activity Series for Metals 1.) Place a reaction plate with at least 24 wells on a piece of white paper and make sure there are 6 wells across and 4 wells down. 2.) Place a test tube in every well 3.) Label each test tubes as following: 4.) Put 1mL of Copper(ll) nitrate solution into wells B1, C1, and D1 using a pipet 5.) Put 1mL of magnesium nitrate solutions in wells A2, C2, and D2 using a different pipet 6.) Put 1mL of lead nitrate solution in wells A3, B3, and D3 using a different pipet 7.) Put 1mL of zinc nitrate solution in wells A4, B4, and C4 using a different pipet 8.) Put 1mL of silver nitrate solution in every test tube in column 5 9.) Place a piece of copper metal in every test tube in row A 10.) Place a piece of magnesium metal in every test tube in row B 11.) Place a piece of lead metal in every test tube in row C 12.) Place a piece of zinc metal in every test tube in row D 13.) Swirl every test tube one by one and make observations 14.) Observe every test tube once a while within 10 mins 15.) Determine whether a reaction has occurred or not? Part 2. Determine an Activity Series for Some Halogens 1.) Label 3 test tubes as Cl 2, Br 2, and I 2 2.) Transfer approximately 1mL of Cl 2 in the labeled test tube 3.) Transfer approximately 1mL of Br 2 into the Br 2 test tube using another dropper

3 4.) Transfer approximately 1mL of I 2 to the I 2 test tube with a pipette 5.) Add 2mL of mineral oil into each test tube 6.) Cork all three test tubes 7.) Shake each of them for 10 seconds 8.) Observe the change in the test tube 9.) Record the data 10.) Label 3 more test tubes as NaCl, NaBr, and KI 11.) Transfer approximately 1mL of 0.1 M NaCl to the NaCl test tube 12.) Transfer approximately 1mL of 0.1 M NaBr to the NaBr test tube 13.) Transfer approximately 1mL of 0.1 M KI to the last test tube 14.) Add 2mL of mineral oil into each test tube 15.) Cork all three test tubes 16.) Shake each of them for 10 seconds 17.) Observe the change in the test tube 18.) Record the observation 19.) Repeat step 1 to 19 for two more times 20.) Arrange the test tube so that there s 6 test tube in the front of the rack with 2 Cl 2 test tubes in the left, 2 Br 2 test tubes in the middle, and 2 I 2 test tubes in the right 21.) Label the test tubes as 1-6 from left to right 22.) Add 1mL of NaBr to test tube 1 and 6 23.) Cork the test tubes 24.) Shake both test tubes for 10 seconds 25.) Record the observation 26.) Add 1mL of KI to test tube 2 and 4 27.) Repeat step 23 to ) Add 1mL of NaCl to test tube 3 and 5 29.) Repeat step 23 to 25 Results: Cu (s) + 2Ag + (aq) 2Ag (s) + Cu 2+ (aq) Mg (s) + Cu 2+ (aq) Cu (s) + Mg 2+ (aq) Mg (s) + Pb 2+ (aq) Pb (s) + Mg 2+ (aq) Mg (s) + Zn 2+ (aq) Zn (s) + Mg 2+ (aq) Mg (s) + 2Ag + (aq) 2Ag (s) + Mg 2+ (aq) Pb (s) + Cu 2+ (aq) Cu (s) + Pb 2+ (aq) Pb (s) + 2Ag + (aq) Ag (s) + Pb 2+ (aq) Zn (s) + Cu 2+ (aq) Cu (s) + Zn 2+ (aq)

4 Zn (s) + Pb 2+ (aq) Pb (s) + Zn 2+ (aq) Zn (s) + 2Ag + (aq) 2Ag (s) + Zn 2+ (aq) Cu (s) Part 1. An Activity Series for Some Metals Cu 2+ (aq) Mg 2+ (aq) Pb 2+ (aq) Zn 2+ (aq) Ag + (aq) No reaction Cu is oxidized. Mg (s) Pb (s) Zn (s) Color of Mg metal fades along the reaction. Bubbles forming. Cu is reduced. Color of the Cu solution fades away. Pb is oxidized. Cu is reduced. Slow reaction. Zn is oxidized. Cu is reduced. Bubbles form during the reaction. Pb is extracted. Pb is reduced. Medium reaction (slower than Ag). Zn is oxidized. Pb is reduced. Slow reaction. Zn is reduced. Little reaction occurred after a long period of time. Pb is oxidized. Zn is reduced. Fast Reaction. Fast Reaction. Pb is oxidized. Zn is oxidized. 2Br - (aq) + Cl 2 (g) Br 2 (g) + 2Cl - (aq) 2I - (aq) + Cl 2 (g) I 2 (g) + 2Cl - (aq) 2I - (aq) + Br 2 (g) I 2 (g) + 2Br - (aq) Part 2. An Activity Series for Some Halogens Halogens Color in Mineral Oil Halide Ions Color in Mineral Oil Cl 2 Colorless in mineral oil NaCl Colorless Br 2 From pale yellow to orange yellow NaBr Colorless I 2 From light yellow to pink/purple color KI Colorless

5 Part 2. Reaction Data Table Reactants Cl 2 (aq) Br 2 (aq) I 2 (aq) Cl - (aq) Br - (aq) I- (aq) Orange on top with milky color on the Different color from Cl 2 in Br is oxidized. Cl is reduced. Dark purple color on the top with a brownbronze color in the bottom with some purple dots. Different from Cl 2 in I is oxidized. Cl is reduced. Light orange on top while colorless on the Similar color to Br 2 in Magenta color on top with yellow oil-like color on the Have small purple dots on the Different from the Br 2 in I is oxidized. Br is reduced. Light purple color on top while colorless on the Have a purple dot on the Same color as the I 2 in Milky pink-purple color on top. Colorless on the bottom with many little dots of pink-purple color. Similar color to the I 2 in Experiment Magnesium Zinc Lead Copper Silver Metal Activity Series Textbook Chemistry: The Central Science (11 th Edition) Magnesium Zinc Lead Copper Silver Experiment Chlorine Bromine Iodine Halogens Activity Series Textbook Chemistry: The Central Science (11 th Edition) Chlorine Bromine Iodine

6 Analysis: Both the experiment and the book showed the same activity series. They both showed that magnesium is the most reactive of all five metals while silver is the least reactive as well as the easiest to be oxidized. This is because the reactivity of an element increases from top to bottom because the ionization energy decrease thus it became easier to be oxidized. To determine that a reaction occurs in the halogen, the observation must be made from the color of the solutions. If a reaction occurs, the color of the halogen solution will change. Halide ions should not dissolve in mineral oil because mineral oil is nonpolar where as the halide ions are. For liquid, the rule for dissolving is that nonpolar liquid dissolves in nonpolar liquid while the polar liquid dissolves in polar liquid. Solvent extraction is the separation of compounds base on their solubility. In part 2, this technique was used in order to separate the chlorine solution and the chloride ions apart. This was done by adding the mineral oil to the test tube so the chlorine solution will be dissolved in Thus, the chlorine solution will be separated from the chloride ions which do not dissolve. It was necessary to test the halide ions for their color in mineral oil because otherwise, what caused the colors would not be known. It could be the reaction between the halogen molecules and the halide ions. However, it could also be that the color of the halogen molecules in mineral oil and the halide ions in mineral oil were mixed together causing a different color. There would be no difference in case calcium bromide was used instead of sodium bromide. This is because the alkali metals in compounds are spectator ions and do not affect the reaction. Conclusion: The hypothesis of is true. The experiment actually helped confirm reactivity of metals and halogens. There could have been several errors during the course of the experiment. An error could be that the test tubes were not clean and caused the color that was apparent to be affected by the contaminants. This would caused the color to be altered from what it should have been. Another error could be that the color observed was incorrect. The colors were blending into each other, so it was hard to determine which color was which. Thus, it could be that the color shown from the reaction was thought to be from the halogen mixing with mineral oil and so was thought that no reaction had happened. In the future, the test tubes should be made sure that they were clean. Also, when determining the colors, they should be observed by others as well to make sure whether a reaction had occurred or not.

Single replacement reactions

Today s focus. Single replacement reactions 1. Learn to predict Single replacement reaction If and when a reaction occurs, what are the products? 2. Learn to write Single replacement reaction: (i) Balanced