An unidentified compound was found in a landfill and the group was ordered to investigate and identify the unknown substance. Figuring out the physical and chemical properties was needed in order to make predications on how the compound might behave. Syntheses of the compound were devised to figure out cost effectiveness, safety, and potential yield of the newly identified compound. Final results established that the unknown compound was NaCl. (1) Initial observations concluded that physically the unknown compound consisted of minuscule white but somewhat colorless crystals. As shown in Table 1, for the solubility test, the unknown compound was put into the three solvents toluene, acetone and water. When mixed with toluene and acetone, the …show more content…
This discovery was found through a flame test. When the unknown compound was burned, a bright, vibrant orange flame color resulted. According to the lab manual chart, a compound that lets off an orange colored flame contains sodium (1). To confirm that the compound did in fact contain sodium, 4 additional flame tests were performed: sodium, potassium, magnesium and calcium. As seen in Table 2, both the unknown and sodium produced a consistent orange flame. Potassium omitted purple light, magnesium showed no change in color, and calcium produced a red light. When heated, due to the excited movement of the electrons specifically in the metal ions within the compound, flame colors are produced (2). The structure of a sodium ion in its ground state is 1s22s22p6 (6). When heat is applied, its electrons then gain energy giving them the ability to jump into empty orbitals at high levels (2). Once the electrons reach a higher level however, they become unstable. The electrons then usually fall back, sometimes at different stages, to where they originally were (2). A certain color corresponds to the particular amount of light energy being released with each jump that is occurring (4). A spectrum of colored lines is produced. For sodium, the difference from one energy level to the next corresponds to the wavelength of orange; therefore it produced an …show more content…
A formation of a white precipitate (AgCl) showed the presence of the chloride ion, Cl-. As the lab manual states, if a precipitate is formed, this test ultimately gives positive results for a halogen or sulfate, since silver salts are also insoluble (1). However, shown in Table 3, when mixing the unknown to find nitrate, carbonate, and sulfate, no positive results were produced. For the anion test, a white precipitate of silver chloride (AgCl) was formed when a solution of AgNO3 was added to the solution of NaCl. In this double-displacement reaction, all the states of the reactants are aqueous, which means they are dissolved in water (6). The insoluble precipitate, AgCl, is a solid. NaNO3 is aqueous because it's soluble in water. AgCl precipitated out of the solution because it's insoluble in water (7). If an ion is insoluble, then it forms a solid with an ion from the other reactant (7). The chemical equation
(i.e., what was the evidence of reaction?) When the piece of magnesium come in contact with the flame, it ignited and emitted an intense bright white light. The light was so intense that it was painful to look at. Furthermore, after the metal was done burning the piece of magnesium changed color and consistency. Before the reaction it was a dull gray, malleable piece of metal.
Is dark blue color color going to grayish black . 2nd in commercial value is pyrolusite. This mineral is thought to have been deposited by ground water carrying manganese.
Untested Victims Bailey Votto 4/19/16 Margaret Oakes Paper 4 Draft #2 When the two solutions, sodium chloride (NaCl) and silver nitrate (AgNO3) react, a soluble sodium nitrate (NaNO3) and a precipitate silver chloride (AgCl) form. While this reaction is not a common occurrence for most of us in our daily life and work, it is in a forensic science lab. This chemical reaction is just one of the many techniques used to unveil fingerprints in a crime scene. Unfortunately, fingerprints are not always left or able to be found. In that case, new chemical procedures must take place.
Have you ever wonder how does a crime scene investigator, known as a CSI, discover blood spatter on different fabrics, which is not visible to the human eye? The key is bluestar. According to the article “Influence of Bluestar Reagent on Blood Spatter Stain of Different Fabrics” by Arnon Grafit, bluestar is a “luminol-based reagent that is applied by spraying on surface.” Not only that, but “it helps obtain DNA and to analyze spatters patterns. By analyzing the article the reader is able to understand how bluestar works through the rhetorical techniques used.
1. For the unknown light source, it had almost every color, so it might have been be mercury because they have similar color beams and their color from the naked eye appeared as purple, which mercury, a light blue, is very close to in terms of it's color from the naked eye. For the unknown flame crystals, it may NH4+ because the colors that appeared are very similar to the crystals. 2. Chemicals have to be heated in the flame for the color to emit because heat adds energy to the substance making the electrons more excited, allowing for the electrons to transition faster. 3.
These electrically charged particles then react with gaseous particles, such as nitrogen or oxygen, inside the Earths atmosphere, forming beautiful coloured waves over the sky. The collisions cause the electrons to become excited and comprise of very high energy levels, once they return back to normal, the atoms emit distinct wavelengths of visible light. The array of different colours are produced depending on the wavelength of light emitted. This is determined by the specific atmospheric gas, its electrical state and the energy of the particle that hits the atmospheric gas. The most common auroral colour is yellowy-green with pink wisps on the edge, this produced by oxygen molecules approximately 100 to 200 kilometres from the earths surface.
The heat from the steam evaporates the water and a white chemical called Ammonium Paratungstate or APT - (NH 4 ) 2 . (H 2 O) x .WO 4 is precipitated. Application of high heat in a calciner causes the compound to reduce to a blue oxide which is approximately WO 3 O 11 . Pure tungsten oxide is WO 3 and yellow.
These color changes indicate a chemical change, which show that a reaction had occurred. In the first step when o-vanillin and p-toludine, imine was formed. The color change from green to orange suggests that imine appears as orange colored. In the second step, the addition of sodium borohydride reduced the imine into another derivative, which was yellowish lime color. The solution turned clear when acids and anhydrides was added, which indicated the precipitate were dissolved.
Chemical compounds that are available to determine are CaCO3, CaCl2, Ca(NO3)2, mgCl2, MgSO4, KCl, HCl, HC2H3O2, KNO3, K2SO4, NaC2H3O2, Na2CO3, NaCl, Na2SO4, HNO3, H2SO4, HNO3, H2SO4, NH4Cl, (NH4)2SO4, K2CO3, 0.1 M AgNO3, 0.2 M BaCl, Mg(s), NaOH, and KOH. To start this experiment, start with the flame test by gathering a Bunsen burner and a Nichrome wire. Connect the Bunsen burner with a rubber tube to a laboratory gas. To prepare solutions for the flame test, weigh out 0.205 gram of Unknown Compound using an analytical balance and mixed it into a 140 mL beaker filled with 20 mL ionized water. Ensure that solid is completely dissolved using a stirring rod.
The reason why this color tends to be a positive color is because of its bright
The death of Caylee Anthony June 2008, Caylee Anthony, a 3 year old girl goes missing, her disappearance is not brought to police attention for 4 weeks from her grandmother, Cynthia Anthony, last saw her. It is Cynthia Anthony who places the call to the police and informs them that her daughter Casey has told me her that Caylee’s nanny has kidnapped her and has been trying to find her on her own. When Caylee’s mother, Casey, spoke to police she told them that she last saw her daughter on the 9th of June, 2008, when dropping her off with the nanny. Casey told the police that Caylee’s nanny was named Zanieda Fernandez-Gonzalez and provided an address. On searching the address the police found that the apartment had been vacant for a couple
10- Pour out the contents in the test tubes and wash them out 11- Pack up your materials Results-Flame test Cation Flame Test A= Calcium Vibrant orange color with a hint of yellow Calcium B=Copper Forest green color with a hint of orange Copper Results- Precipitate Test- Anion Halide Test (Silver Nitrate) Sulfate Test (Barium Chloride)
I chose group 6A and I saw something very interesting thing. The atomic numbers all went up by 8. The ionic radius was always going up but not by any pattern. With the ionization energy and the atomic number the ionization energy was going down with each element where the atomic was going up by 8. These relationships exist to show how these elements all fit into group 6A, they all have to have a relationship or they will not work.
Properties of Ionic and Covalent Substances Lab Report Introduction The purpose of this lab was to determine which of the following substances: wax, sugar, and salt, are an ionic compound and which are a covalent compound. In order to accurately digest the experiments results, research of definitions of each relating led to the following information: ionic compounds are positive and negatively charged ions that experience attraction to each other and pull together in a cluster of ionic bonds; they are the strongest compound, are separated in high temperatures, and can be separated by polar water molecules. A covalent compound forms when two or more nonmetal atoms share valence electrons; covalent compounds are also
Assignment 5 - Neurotoxicity 1. Describe the differences in the physical properties of organic, inorganic and elemental mercury (6 marks) Elemental mercury is also known as metallic mercury. It is shiny and silver-white in colour. At room temperature, elemental mercury is in a liquid state and some of this liquid mercury will evaporate and form mercury vapor. The vapor itself is colourless and odorless.