Investigating the various phenomena which occur when monochromatic light undergoes diffraction Title: Determine the wavelength of a monochromatic light source (laser). Measure the groove spacing of a CD and the diameter of powder spores using diffractive methods. Aim: The aims of this experiment are to determine the wavelength of the monochromatic light source and to determine the groove spacing of a CD and the diameter of the Lycopodium powder. Introduction: There are three parts to this experiment in the first part a diffraction grating is used to diffract light from a laser (monochromatic source of light). By measuring the angles of diffraction and by calculating the grating spacing, the wavelength of the light may be calculated.
EXPERIMENT 6 Title Kinetics of Chemical Reaction – Iodination of Cyclohexanone Aim To determine the value of the rate constant, k and order of reaction, a, b and c, and also to suggest a mechanism which agrees with the rate equation that has been obtained. Background Theory The basis of the theory of absorbance is as follows: Io ―――――→ sample ―――――→I if Io = I, no absorbance occur Io > I, the sample absorbs certain amount of light wave Io < I, the sample emits certain amount of light of certain wave length. THE HALOGENATION (IODINATION) OF KETONES (CYCLOHEXANONE) This experiment examined the rate of iodination of cyclohexanone in an aqueous medium. To increase the amount of iodine in the solution, iodine is converted to a more soluble complex ion, I3- by the addition of excess iodide ion: I2 + I- →I3- One of the characteristic reactions of ketones is the substitution of a halogen for one of the hydrogen is adjacent to the ketone group. The net reaction is: This reaction has been studied extensively and occurs for a wide variety of ketones.
As Model Science (2011) explains, the experiment will show that as the salt with the metal is “burned, the electrons will be excited (i.e., move to another energy level) and as these electrons fall back from one energy level to another, they will emit photons of light. These photons will have different colors depending on the element and its discrete energy levels”. In other words, “different wavelengths of light (colors) will be emitted when the electrons of different elements go down the step(s) between their energy level(s). In addition, each element will have its own set of energy levels and therefore each will have its own color or set of colors (Model Science, 2011)”. As an example, Model Science (2011) provided “sodium burns orange, potassium -purple/blue, barium - green, and lithium – red”.
This will help determine the types of ions present in the water sample. Ions also absorb light differently according to the concentration of the ions in the solution. Using absorption spectroscopy the absorption rate is used to determine which ions are present in the solution and at what concentration. The equation m1v1=m2v2 will be need where m1 and v1 are the initial concentration and volume, and m2 and v2 and the final concentration and volume. Experimental: List of Chemicals 0.5 M NaCl solution 0.5 M LiCl solution 0.5 M KCl solution 0.5 M CaCl2 solution 0.5 M SrCl2 solution Fe/Cu solution containing 400 ppm Cu2+ and 20 ppm Fe3+ in SCN- solution 20 M iron(III) nitrate solution
Halides Lab: Background information: Halide ions are reactive and useful. Salts are positively charged ions (metals) combined with any negative ions (nonmetal), and when placed in a solution (water) it separates into the cations and anions that made it up. The Purpose of this lab is to find out how the Halides react with the indicators, and to determine the identity of the two unknown solutions (A and B). Color of solutions prior to experiment: NaF | NaCI | KBr | KI | Unknown A | Unknown B | clear | clear | clear | clear | clear | clear | Color of indicator prior to experiment: 5% Bleach (NaOCI) | 0.2 M Na2S2O3 | 0.1 M AgNO3 | 0.5 M Ca(NO3)2 | clear | clear | clear | clear | Halide solutions | NaF | NaCI | KBr | KI | unknown A | unknown B | Test 1: Ca(NO3)2 | Cloudy White (Nothing) | Clear | Nothing | light yellow (Nothing) | Nothing | Nothing | Test 2, Part A: AgNO3 | clear (Nothing) | Milky White | Gold (Cloudy yellow) | milky green (Cloudy yellow) | turned white, film developed on top layer | Milky | Test 2, Part B: add Na2S2O3 to test tube from part A | Dark Orange/brown | Clear | Dark Gold(precipitate yellow then clear) | milky green (no change) | white precipitation, settled on bottom | Milky | Test 3: NaOCI (Bleach) | Clear (Nothing) | Nothing | Nothing | Orange (Clear) | Nothing | Orange | Unknown A is identified as NaCI (Sodium Chloride), because in test#1 the solution turned a cloudy white color when Ca(NO3)2 (Calcium nitrate) was added. In the first part of test#2, when AgNO3 (Silver nitrate) is added, the solution turned white, with a thin layer of film developing on the surface.
What are the identities of the substances found after electrolysis and heating? The identities of the substances found were Iodine, Iodide ion (I-), Triodide ion(I3-), Zinc metal and Zinc ion(Zn2+) Post Lab questions: 1. What did this experiment convincingly show about the composition of the white solid? I put that the experiment showed us the white substance was comprised of Zinc ions and iodide ions, and that the two ions and be separated back into their respective elements 2. During the electrolysis, a gray solid formed on the negative wire of the battery and the dark red solution formed at the positive wire of the batter.
We resulted that lead, silver, and copper are the strongest oxidizing agents, and that magnesium and zinc are the weak oxidizing agents. The strong oxidizing agent oxidized the weak oxidizing agent and in turn the strong oxidizing agent got reduced while oxidizing the weak agent. When a reaction occurred, the solid metal reduced the ion, and in turn made it the more reactive metal. In part two we used a solvent extraction technique to derive an activity series for the halogens. With the use of this technique we placed chlorine, bromine, and iodine into solutions containing chloride, bromide, and iodide.
Experiment#2 “Separating the Components of a Ternary Mixture” By Mohammad Bazargan Lab partners: Aaron Radtke, Kevin Campbell, Austin Gilchrist Instructor: Professor Mundell Section #: 12 Sep/14/2011 Abstract In this laboratory, we used physical and chemical properties to separate the components of a ternary (three substances) mixture. We also determine the percentage of each substance in the mixture. The percentages are the following,38.2% NaCl, 40.45% SiO2, and 72.84% CaCO3.The mentioned substances were all separated using methods such as filtration, evaporation and reaction with other chemicals which will be explained throughout this report. Intro Mixtures are \ physical combinations of two or more substances where each substance keeps its own chemical identity. Mixtures can be classified as either homogeneous or heterogeneous.
The technique of infrared spectroscopy, in both the solid and solution phases, has proved to be of very useful in these studies. In this experiment mononuclear metal carbonyl chemistry is observed with Molybdenum hexacarbonyl, [Mo(CO)6] (2). From there the synthesis pathway with each transition along the way being analyzed. This sequence of reactions is used to help one achieve a better understanding of the factors responsible in determining which ligands will be exchanged in a ligand substitution reaction involving an octahedral complex, and what might the dominant product stereochemistry be. Each of the three reactions are heated at reflux, cooled, and filtered, yielding their respective products.
The components of the sample will be separated on the basis of their ranging physical and chemical properties, imparting different affinities for the two phases. Thin layer chromatography (TLC) was the first chromatographic method for assessing phospholipids, and is commonly used today.