Thermochromism in Ink Chemistry

4. There are other types of reagents used to determine what type of biomolecule a substance is. For example, copper ions present in Benedict’s reagent reacts with the free end of any reducing sugars, such as glucose, when heated. Originally blue in color, these copper ions are reduced by the sugar, and produce an orange-red colored precipitate. Alternatively, iodine-potassium iodide (IKI) may also be used when working with starch. IKI contains special tri-iodine ions which interact with the coiled structure of a starch

Boynton, R.M. 1987. Color. In McGraw-Hill Encyclopedia of Science & Technology (Vol. 4, 165-166) McGraw-Hill, Inc.

This could be improved by utilizing an inert atmosphere of solely nitrogen. Melting the compound resulted in an intensely dark purple liquid. This is a result of the resonance stabilized radical being formed by the homolysis of the carbon-to-carbon bond validating the photochromic properties. The colour change further substantiates that the desired product was produced despite the inaccuracies in melting point values. Homolytic cleavage of the dimer prepared by solvation with toluene results in a deep purple solution confirming the formation of the resonance stabilized radical.

It is a chemical reaction where the colors of both solution and iron strip changed. It is

A cell, the building block of all living organisms, is composed of four fundamental biomolecules: proteins, carbohydrates, sugars and lipids. Proteins provide a vast amount of functions cells such as they serve as enzymes, provide structural support to cells, and act as antibodies. Reagents are used to spark a chemical reaction. The reagent used to detect protein traces in a substance is Biuret’s. Biuret’s will turn purple if proteins are present and blue if they are none. Biuret’s copper particles, have a charge of +2, are diminished to a charge of +1 when peptide bonds, which are in proteins, are present, creating the color change. Polysaccharides, which are carbohydrates, are most notably known to provide energy to the body, but they also help in breaking down fatty acids. Iodine is the reagent used to determine whether a substance has starch in it. The iodine/starch complex has energy levels that are only for retaining unmistakable light, giving the complex its extraordinarily dark black-blue shade. If there is no starch found, iodine will remain its natural yellowish-brownish color, but if starch is present, iodine will turn blue-black. Monosaccharides, which are sugars, like polysaccharides, provide the body with energy. To detect monosaccharides, the reagent, Benedict’s, is used. Benedict’s reagent is added to a test tube, then it is placed in

Amethyst is purple quartz; the color is caused by iron (Fe4+) impurities. Azurite is a copper mineral. Calcite is a very common and widespread mineral and has highly variable forms and colors. Lodestone is a natural magnet. Mica is a sheet silicate. Rose quartz is translucent and a variety of the silica mineral quartz, found in pegmatite. Talc almost always found in foliated masses in metamorphic rocks with many carbonate minerals. Pyrite is a very common mineral. The brassy-yellow metallic color of pyrite has lead people to mistaking it for Gold, so its common nickname is

When analyzing the IR spectrum of Ruthenium complex with DMSO, the prominent peak is presented at 1105.54 cm−1. This peak indicates that S=O bonded in DMSO. For DMSO, the frequency is around 1050 cm−1. From our spectra obtained for DMSO where the S=O peak is at 1017.65 cm−1. Since the bond appears at a higher frequency, this shows that the bond is strengthened by the reaction. This indicates that when the copper metal was combined with DMSO, it bonded with the Sulfur atom. Combining ruthenium with sulfur atom caused it to donate a pi electron as a back donation.

Introduction: I know prior to doing this experiment that iodine mixed with starch creates a dark color and that most objects, organic and inorganic, naturally experience isotonic reactions.

3) Cooling the contents decreases the amount of heat in the system. Equilibrium will shift to the left causing the solution to become light red.

This reaction is going in the reverse direction. This shows Le Chatelier’s Principle as it explains that when a system at equilibrium is subjected to a change that upsets the equilibrium, the system will neutralize the disturbance to restore equilibrium to the system. The reaction is moving in the reverse direction as when HCl is added to the solution, there becomes an excess amount of products because more molecules are being added. When the concentration of the products was increased, there were a greater number of effective collisions between the molecules in the products. This then increased the rate of the reverse reaction. Due to the excess amount of products, the system shifted in the reverse direction in order to decrease the products. By moving in the reverse direction, the system was able to produce more reactants to reduce the products. This brought the system back to

Every 4th of July, many people go out at night and spend hours watching firework shows. Most of us are content to simply enjoy the pretty colors and sparks, without questioning the chemistry behind the spectacle, but have you ever really thought about how fireworks produce such vibrant colors? The colors emitted when a firework explodes come from an aerial shell inside the firework that contains explosive chemicals and metallic salts. These colors appear to us because of luminescence. Luminescence occurs as a result of the valence electrons in the metal salt atoms moving and changing positions. The explosion of fireworks is not a miracle; it’s simply chemistry at work.

1- Different elements give off different colors when heated because electrons go farther the nucleus, or to an upper energy level, and once they go back to their original orbit (energy level), they release colors because of the amount of energy released. This also happens because different elements are in different orbits and they hit different orbits as well.

Results: For part one of Lab 3a, Day one, the beginning unknown mineral was a blue-green color. The mineral was charcoal colored after the roasting process. Roasting caused the mineral to lose mass. The lost mass was due to release of gas.

Pigments-pigments change the colour from the natural colour to make it more pigmented which is making the colour stronger and

2. Miller, F.; Wilkins, C. Infrared Spectra and Characteristic Frequencies of Inorganic Ions. Ph.D. Dissertation, Mellon Institute, Pittsburgh, PA, 1952.