After that, dissolve the sample in 2 mL of deionized water and shake the test tube for 1 to 1 ½ minutes to dissolve the solid. Place another dry test tube in a 50mL beaker and weigh it. Find a bottle of barium iodide and record the name and molar mass. Then, weight out either anhydrous barium iodide or barium iodide dehydrate into this test tube and dissolve is it in 2 mL of deionized water. Pour the contents of one of the test tubes into the other and a reaction should occur and you should see a white precipitate of barium sulfate form.
(h) "Hard" water contains a high concentration of calcium ions. Suggest a way to make hard water "softer: Answers: a) It could have been improved if the experimental design said " you have to place seven different nitrates in three different sodium solutions to see if a reaction occur." b) With my evidence silver nitrate was the would the cation that would make most of the anions create a precipitate. c) Chlorine can selectively remove silver ions from a solution because silver has a positive 1 charge and chlorine has a negative 1 charge so when they react it is a perfect
5mL of acidified water will be measured, using a graduated cylinder, and will be transferred to the R tube, and will be immediately vigrously mixed with the reactants. Once the solution turns to an orange or red-brown color, a pipet will be used to quickly remove 30 drops of the solution, then transferred to the C tube, and the mixing will resume until the solution is close to room temperature. The solution will be filtered into the P tube, and the solution that is left in the R tube should be washed three times with 1mL of acidified water each time. The water should then be poured into the P tube, leaving the solid in the R tube. Using a test tube holder, heat the R tube over the Bunsen burner, moving the tube in a circular motion until all the water has evaporated.
Once a light blue solution remained, 5mL of distilled water was added. This solution was then placed onto the magnetic stir plate and magnetic stir bar was placed in liquid solution. Then to the solution .75g of zinc was added to solution. Then once the solution was colorless, the solution was removed from magnetic stir plate and the liquid was decanted away from the copper. Then 5mL of HCl was added to copper to completely remove all traces of zinc.
Focus Question Should chemists prepare Zinc Iodide, from its elements or from a Double Replacement Reaction between Barium Iodide and Zinc Sulfate? -To put things into perspective in terms of cost efficiency, zinc granules cost about $62.50 per kilogram or $.0625 per gram. Also, Iodine chips cost about $.1498, Barium Iodide Dihydrate costs about $.886 per gram, and Zinc Sulfate Heptahydrate costs about $.0405 per gram. According the chemical reaction listed below, the double replacement reaction creates a solid Barium Sulfate precipitate This means that the ZnI2 is less pure than it would be from just the Zinc and the Iodine. With the elemental reaction you get ZnI2 as your only product thus indicated that it is “pure” Zinc Iodide.
Turn on the hot plate to a medium heat. Wait until all the liquid has evaporated from the substance and then record the color of the dried substance. 6) Repeat steps 1-5 using each of the three other substances. NOTE: Make sure to wipe down all the materials before they are reused. Compounds | Solubility in Water | Solubility in Alcohol | Color if Soluble in H₂O | Conductivity(Scale 1-4) | Color When Dry | Melting Point (°F) | Sucrose | Yes | No | Transparent | Medium (2) | Brown | 366.8 | Sodium Chloride | Yes | No | Transparent | High (3) | Crystallized, Clear | 1474 | Sodium Carbonate | Yes | No | Mostly Transparent | High (3) | White | 1564 | Salicylic Acid | No | Yes | N/A | High (3) | White | 318.2
White precipitate shows the presence of chloride (Cl-). Chloride anion equation: HCl(aq) + AgNO3 (aq) → HNO3 (aq) + AgCl(s). The nitrate anion test involves cooling a mixture containing 1 mL of test solution and 3mL 18M H2SO4. 2mL is poured down the inner test tube side and the presence of a brown ring shows nitrate (NO3-) to be present. The carbonate anion test mixes 1 mL of test solution and drops of 6M HCl.
Calculations To figure out the amount of zinc sulfate that we had to add to the water, so that the molarity of the solution would be 0.20 g/mol, we did the following steps: First we calculated the amount of the zinc sulfate to add in moles. To do that we multiplied the concentration (c) of zinc sulfate with the total volume (V) of the solution. The answer was amount of zinc sulfate to add in moles (n).
That told me it was the end point of the titration. When I added the base to the acid, I noticed that the indicator in the acid turned pink after reaching the end of the titration. Procedure Part 1: *First I had to measure the pH of 0.1 M hydrochloric acid. Get a 100 mL beaker from the equipment menu Right click on the beaker, select chemicals, and add 50 mL of 0.1 M hydrochloric acid. Measure the solution by right clicking on the beaker and choose pH meter *Then I had to measure the pH of 0.1 M sodium hydroxide Get a 100 mL beaker from the equipment menu Right click on the beaker, select chemicals, and add 50 mL of 0.1 M sodium hydroxide.
Adequate separation will have occurred when the cresol red dye front has moved at least 50 mm from the wells. Gel may be stained either with 1 µg/ml ethidium bromide for 10 minutes or 0.05% methylene blue (or proprietary) stain for 30 minutes, followed by 20-30 minutes destaining with water. * If adding Bromophenol Blue loading dye to sample: do not add the loading dye to the entire sample, leave 10µl of sample without loading dye if you will be sending sample in for