Magic marker inks are often mixtures of several compounds. Paper chromatography is a common method of separating various components of a mixture. After separation, you can observe the different colors that make up a particular color of magic marker ink. You can also calculate a ratio Rf, which compares how far each compound traveled to how far each solvent (substance that dissolves another substance) traveled during the experiment. Rf = Ds/Df Ds = Distance traveled by the compound Df = Distance traveled by the solvent Materials: coffee filter, tape, isopropyl alcohol (rubbing alcohol), water, 3 different color magic markers (not permanent); 3 identical tall, narrow drinking glasses; metric ruler, 3 pencils Pre-lab Questions: List one extensive and one intensive property of marker ink.
In the first part, five 100 mL flasks of 5 mL ligand solution, 5 mL 2 M sodium acetate, 4 mL 3 M NH2OH, and 1-5 mL Fe2+ solution are diluted with water. The absorption spectrum for varying concentrations of Fe2+ are measured using a spectrophotometer and the data is graphed in Excel. The slope of the line is ε in the Beer-Lambart equation A = εcl. In the second part of the experiment, eleven flasks containing diluted stock solutions of Fe2+ and ligand are mixed with 5 mL 2 M sodium acetate and 4 mL 3 M NH2OH and diluted with water. The absorption spectrum is measured using a spectrophotometer and the data is graphed in Excel.
Materials & Methods Identifying the unknown compound solution (#2314) first required the identification of each individual solution. One drop of each solution was added to five individual wells of a spot plate. Next, three drops of 3M hydrochloric acid (to be referred to from now on as HCl). The spot plate was then cleaned, and the procedure above was recreated two more times, the second test done by adding 3M ammonium hydroxide (NH4OH), and the third by adding 1 drop of dimethylglyoxime (DMG). All color observations were recorded and compared to the known behaviors of the focus metals.
Predicting an Unknown from Logic Trees Project 2 Report Ashley Garcia* Ayland Smith Introduction The purpose of the project was to use elimination and confirmation tests on several anions and cations to form a logic tree. Cations used in part 1 are potassium, iron (III), zinc (II), copper (II) and cobalt (II), and the anions in part 2 are chloride, carbonate, nitrate, and sulfate. The unknown contains both a cation and an anion. The logic trees from part 1 and part 2 were then used to identify an unknown. Materials and Methods Part 1 For the cation elimination test first 10 drops of potassium, iron (III), zinc (II), copper (II), and cobalt (II) were added to 5 centrifuge tubes and the color was recorded.
Chromatography: Separating Mixtures Introduction: Magic marker inks are often mixtures of several compounds. Paper chromatography is a common method of separating various components of a mixture. After separation, you can observe the different colors that make up a particular color of magic marker ink. You can also calculate a ratio Rf, which compares how far each compound traveled to how far each solvent (substance that dissolves another substance) traveled during the experiment. Rf = Ds/Df Ds = Distance traveled by the compound Df = Distance traveled by the solvent Materials: coffee filter, tape, rubbing alcohol, water, 3 different color magic markers (not permanent); 3 identical tall, narrow drinking glasses; metric ruler, 3 pencils Pre-lab Questions: 1.
The phosphate activity found in our extract would be acidic because the pH is low. 4. (4pts) Write an abstract for this experiment. An abstract is a short paragraph (three to five sentences) that communicates the purpose of the experiment and states the specific conclusions determined by the experiment. Do not go into detail about the protocol.
Experiment 5: Titration for Acetic Acid in Vinegar Name: Lab Partners: None Date of Experiment: March 25th, 2013 Location: My House Course Number: Chem 112 Abstract: In this experiment the objectives were develop familiarity with the concepts and techniques of titration and to determine the concentration of an acetic acid solution in vinegar. Experiment and Observation: Data Table 1: Quantity of NaOH needed to Neutralize 5 mL of Acetic AcidBrand of Vinegar Used: Heinz White Distilled VinegarLabel Notes: ______________________ | | Initial NaOH reading(Interpolate to 0.1 mL) | Final NaOH reading(Interpolate to 0.1 mL) | Volume of NaOH used | Trial 1 | 9.5 | 1.3 | 8.2 | Trial 2 | 9.7 | 1.4 | 8.3 | Trial 3 | 9.6 | 1.4 | 8.2 | Average volume of NaOH used: | 8.2 | Calculations and Errors: Errors: Calculations: A. Calculate the average number of mL of NaOH used for the 3 trials and record. B. Calculate the Normality of the vinegar using the previously given equation.
Name Section Unknown Laboratory Project – Identification of Unknown Organism Project Set-up (14 pts) Name media type and forms used: Broth tube, Agar slant and agar streak plate Temperature of incubation: 37C with an incubation period of 18-24 hours (lab Manuel- pg 25) List 5 steps/procedures you followed to prevent contamination of your culture. 1. aseptic technique 2. Flaming inoculator 3. heating the tubes 4. not talking over the specimen while you are inoculating 5. close the streak plate when not in the process of inoculating List the 5 procedures you will perform to identify the unknown. 1. inoculate agar slant 2. inoculate
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
Then measure the distance of each pigment starting at the bottom of the pigment origin to the bottom of the separated pigment band. In Exercise 4B: Photosynthesis/ The Light Reaction, chloroplasts are extracted from spinach leaves and incubated with DPIP in the presence of light. The spectrophotometer should be warmed up and set the wavelength to 605 nm. An incubation area should be set up, that includes a light, water flask, and test tube rack. We were provided with two beakers, one containing a solution of boiled chloroplasts and