Pour all the filtrate and washings into a 250cm3 volumetric flask. Make up to 250cm3 with 1.0mol dm-3 sulphuric acid(VI) acid. Stopper the flask and invert several times to thoroughly mix the solution. 5. Fill the burette with 0.005mol dm-3 potassium manganate(VII) solution.
Add a two-gram sample of each of the above compounds to each test tube. 3. Stir the samples. 4. In the chart provided record if each compound is solubility in ethanol.
When the liquid above the precipitate was clear, the solution was tested for completeness of precipitation when a few drops of BaCl2 solution were added from a pipette. Next, filter paper was place into the funnel and streamed with distilled water. A clean 400mL beaker is placed under the funnel and the precipitate was filtered through. When all the precipitate was filtered and removed from the beaker the residue is washed with distilled water. About 3mL of the wash water is collected in a small test tube.
Title: 1pt Stoichiometry Of A Precipitation Reaction 2. Procedure: 2pt (Write the procedure in your own words after you have read the lab manual) Put on goggles the weigh 1.0 of CaCl*2H2O and put it in 100ml beaker. Add 25 mil of water and stir. I will then use stoichmetry to figure out how much Na2CO3 I will need for a full reaction. I will weigh this and put it in a separate cup.
12. Place a paper towel over the drain, pour the content of the well plate, throw the paper towel and rinse the well plate. DATA, OBSERVATIONS, AND CALCULATIONS: Data Table: Oxidation - Reduction | | Reactions | Mg in Na2SO4 | Bubbles | Zn in MgSO4 | Small bubbles | Pb in Zn(NO3)2 | Dark lead changed into lighter color | Pb in FeCl3 | Changed the lead into slight green yellow | Fe in CuSO4 | Changed the iron into orange color | Note: I added more than 10 drops to make sure that the pieces are well covered. QUESTIONS: A. Based on your observations make an activity series of the metals used.
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.
After donning the appropriate safety gear I began by placing 3 separate sets of 10 drops of distilled water into an unused well of the 24 well plate. I added the following chemicals into one of the three sets of distilled water creating three separate chemical mixtures: HCI, Ammonia, and Sodium Hydroxide. I mixed all thoroughly with a toothpick and then sucked the mixtures into separate pipets. These were placed into the 24 well plate for later use. Using the 96 well plate I combined various chemicals together to observe the chemical changes that were created.
Procedure: Mix the two solutions together. Stir by stir bar and stir plate, swirl the mixture in the flask by hand, or mix by transferring the mixture back and forth between the two flasks. Stir until the colorless solution turns blue (about 10 seconds). Clean-Up: Remaining blue solution can be washed down drain with water . Background: For the entire explanation of this demo see Shakhashiri's Chemical Demonstrations, Vol.
The paper was then put into a beaker of a hydrochloric acid, ethanol, and butanol mixture, being sure that the paper does not touch the sides of the beaker, and then topped. After the eluting solution has risen to within two centimeters of the top of the filter paper, the paper was removed from the beaker, dried, and was stained with a staining reagent solution containing potassium ferrocyanide and potassium iodide. This reagent forms colored precipitates or reaction products with many cations, including all of those used in this experiment. The distance of which the spots moved were determined by calculating the Rf value of each substance. The Rf value is determined by following formula: Rf=DL=distance component movesdistance solvent moves This experiment was successful overall, given a few errors.
4. Chlorine, Cl 2, is a strong oxidizing agent found in bleach. 10.0 cm3 of bleach solution was added to 25.0 cm3 of 0.4M Sn2+ solution acidified with sulphuric acid and made up to 100 cm3. 10.0 cm3 of the resulting solution containing the unreacted Sn2+ was titrated against 0.02M K2Cr2O7. Given that 11.40 cm3 of K2Cr2O7 was required for complete oxidation, a) Calculate the numbers of moles of Cr2O7- used.