Dip a cotton swab in each solution and hold to a flame. Observe the color of the flame with the soaked cotton swab. Use the 7 known compounds to determine the unknown ion solution. Data Table: Metallic Ion | Flame Color | Sodium Na+ | orange | Strontium Sr2+ | bright red | Potassium K+ | pinkish/purple | Lead Pb2+ | Did not come with our lab kit | Barium Ba2+ | yellow/white | Copper Cu2+ | green | Lithium Li+ | pink/red bright | Calcium Ca2+ | pink | Unknown (Sr2+) | orange/red | Observations: When passing the cotton swabs soaked in different ions through a flame many colors were noticed. For some of them there was a cracking sound.
* 100% key lime * 50% key lime * 25% key lime 3. This is the formula to produce different key lime concentrations. * M1V1 = M2V2 Preparing of Kirby-Bauer test Materials and apparatus * Broth cultures of P. anvenginosa, E coli, S. aurens and B. spizizenii * Sterile cotton swab * Forceps * Bunsen burner * Whatman filter paper (small piece after punch) * Key lime discs * Parafilm Procedure 1. Swirl the contents of the broth culture of P. anvenginosa until it is equally murky throughout. 2.
The conical flask was then positioned to just under the burettes dropper which had its stopcock opened to allow a medium drip rate and had the sheet of filter paper slipped under it so that the colour could be seen more earily. As it was dripping the conical flask was gently stirred to allow the two substances to mix together. 10.
Drop a very small amount of iodine on a piece of paper and observe what happens to the paper. (Paper has lots of starch in it) The Iodine turned black on the paper. Supplies Needed: -plastic baggie/cheap works well -water (tap is fine—or bottled) -iodine (use caution if you are allergic to iodine/betadine) -cornstarch -measuring cup -about a 2 cup size cup/beaker/bowl—clear would be great Procedure: Fill a plastic baggie with a teaspoon of corn starch and a half a cup of water tie bag. Fill a cup (about a two-cup size)halfway with water and add ten drops of iodine. Place the baggie in the cup so that the cornstarch mixture is submerged in the iodine water mixture.
water, oxygen, nutrients, cellular waste are transported inside, outside the cell or to different cellular organelles. It is easy to observe diffusion by gently pouring a coloured liquid into water. In this experiment I will examine diffusion of a solution in a jelly-like substance - agar. Because both the solution and the agar are colourless I will use agar that had before been mixed with phenolphthalein. This also colourless substance is a commonly used indicator that changes its colour into pink with the presence of a base.
Then by writing a balanced chemical equation and using the titration formula, Nb+Ma+Va=Na+MbVb , the molarity is able to be determined. Procedure: 1) Using the graduated cylinder add 10.0 mL of water into the Erlenmeyer flask. 2) Add 5.0 mL of HCl into the flask using another graduated cylinder because acid goes into water when mixing them. 3) Add three drops of phenolphthalein indicator into the flask. 4) Swirl the flask in circular movements to mix the substances.
The third test will utilize thin layer chromatography to evaluate the purity of the aspirin as well as testing for the presence of leftover salicylic acid or other by products of the reactions. Experimental: Week 1: For the synthesis of the aspirin, 250 mL of water was boiled. 1.5 g. of salicylic acid were poured on a test tube. Then, 3.5 mL of acetic anhydride and four drops of 85% phosphoric acid were added. A cotton ball was placed to prevent vapor escape.
The H2O is retained in the liquid, while SO3 gas is released. Therefore, the concentration of H2SO4 decreases, reaching a concentration of 98.33%. Sulfuric acid boils at 338°C and is the material sold as "concentrated sulfuric acid. It can be used to chemically remove water from many compounds. It dehydrates sucrose (table sugar), C12H22O11, leaving a spongy black mass of carbon and diluted sulfuric acid.
| A light red precipitate was formed. | 4M NH4Cl and concentrated NH3. | Fe3+ + 3NH3 + 3H2O → Fe(OH)3 + 3NH4+ | 6 | Centrifuge the solution and transfer the supernatant by using a pipette. | A yellowish solution was formed. | - | - | 7 | By dissolving the precipitate.
Specimen: The specimen is to be fixed in 10% Neutral Buffered Formalin, and paraffin sections should be cut at four to five microns and placed on Plus (+) slides. The tissue is dried for 20-30 minutes in an oven at 68°C. Deparaffinization and rehydration should be carried out immediately before staining. Positive controls are to be processed at the same time as the unknown test slide. Equipment and Supplies: The equipment and supplies needed are acid cleaned glassware, coplin jars, and an incubator oven.