To browse Academia. Skip to main content. Log In Sign Up. Sherey Mae Balagao. Introduction Dicarboxylic acids are organic compounds that contain two carboxyl functional groups. From an industrial perspective, it is the most important dicarboxylic acid: About 2.
The great majority of the 2. Other industrial uses of adipic acid are the production of adhesives, plasticizers, gelatinizing agents, hydraulic fluids, lubricants, emollients, polyurethane foams, leather tanning, urethane and also as an acidulant in foods. Adipic acid is used after esterification with various groups such as dicapryl, di ethylhexyldiisobutyl, and diisodecyl. Adipic acid otherwise rarely occurs in nature.
Nylon 6,6- a polymer of adipic acid and 1,6-diaminohexane Adipic acid was commonly obtained by oxidation of castor oil with nitric acid splitting of the carbon chain close to the OH groupbut it is also obtained by oxidation of cyclohexanone or cyclohexene. The oxidation of an alkene is an example of an addition reaction. Oxygen atoms in the oxidizing agent add to the carbon- carbon double bond. As a result, the ring opens and the dicarboxylic acid is formed. The purpose of this experiment is to synthesize adipic hexanedioic acid through the permanganate oxidization of cyclohexene and also to gain familiarization of the laboratory method for following the progress of permanganate oxidations.
Results Tabulated results obtained from the procedure, including any necessary computations made with respect to the data is shown below. Accuracy of the overall procedure is important to yield maximum amount of the product.
At first, the original procedure required chromic acid as the oxidizing agent but with chromic acid being dangerous if not carefully handle, potassium permanganate was used as an oxidizing agent instead. This is by the knowledge that 0. The yield obtained from the experiment is 1. This experiment carried out the oxidative cleavage of cyclohexene to produce adipic acid. Cyclohexene, an alkene, is susceptible to oxidation because it has a carbon-carbon double bond which is a site of relatively high electron density.
Oxidative cleavage of alkenes is a well-known reaction. Several reagents are known to react with alkenes which result in complete breaking of both bonds to the carbon atoms. With relatively mild oxidation, only the pi bond of the alkene is cleaved, producing epoxides and 1,2-diols.
More vigorous oxidation can result in the complete cleavage of the carbon-carbon double bond, leading to the formation of various carbonyl compounds, with the specific product dependent on the substitution pattern of the alkene and on the nature of the oxidant used. Reaction of cyclohexene with potassium permanganate under basic conditions results in oxidation. The cyclohexene is oxidized by the permanganate which leads to a ring opening reaction producing adipic acid as the final product.
MnO4 ion attaches to the carbons in the double bond creating two separate Carbon-Oxygen bonds. Then, the resulting molecule undergoes a reaction with water in a series of several steps which are quite complex, to produce a diol molecule 1,2- cyclohexanediol and the compound Manganese Oxide MnO 2 which is a brown precipitate.
But before the 1,2-cyclohexanediol is further oxidized which is the mechanism shown abovethe manganese product actually loses water to form MnO 3 ion which is unstable.
The unstable MnO3 ion undergoes a reaction with water to regenerate the permanganate ion. The permanganate ion that was regenerated is the one that oxidized the diol further. The negatively charged oxygen from the produced molecule attracted the free potassium ions in the solution from potassium permanganate KMnO4.
The reaction is illustrated below: [O] The di-carboxylic salt product is then converted into adipic acid through the addition of concentrated Hydrochloric acid HCl to the solution and then cooling it in a waterbath. The solution is then acidified in order to induce protonation and break the bond it formed with potassium ions.
At the start of the procedure where cyclohexene was added by potassium permanganate, an excess permanganate ions were form at the solution and this excess permanganate ions need to be removed because it could possibly affect or interfere the reactions.
Methanol was added to the mixture which is being heated in a water bath in order to remove the excess permanganate ions in the solution. Through spot tests on filter paper, the removal of excess permanganate ions were being observed.Jump to content. The focus of this guided inquiry laboratory is to foster critical thinking that allows students to design, perform, and interpret experiments.
In addition, the student acquires technical skills that are required for further advancement in experimental sciences. Although an ability to collect and analyze data in a quantitative manner is developed, the emphasis of the course is to provide a qualitative understanding of the basic concepts of chemistry. This is accomplished by demonstrating that chemical principles are derived from experimental data. The goal is to provide students both with a more accurate picture of the scientific process and with skills that are relevant to solving real life problems.
She is Chemistry co-editor of MERLOT where one of her roles has been the establishment of evaluation criteria for online learning objects. Term: Fall July 19, June 5, About the Creators. Nancy Kerner. Columbia University Ph. Columbia University. Jump to: Handouts. Akiko Kochi. Experiment 1- Experimental Determination of Precipitate Identity.
Experiment 1- Introduction. Experiment 1- Optional Reviews and Extensions. Experiment 1- Precipitation Reaction. Experiment 1- Required Background Knowledge and Skills.The abundant flavanol monomers catechins in these extracts were also tested for their inhibitory potential and evaluated against the pharmacological glucosidase inhibitor, acarbose.
Glycemic control is an effective, long-term therapy for individuals with type II diabetes mellitus, reducing the risk of both cardiovascular and neurological complications in the development of the disease 12.
Glucosidase inhibitors are commonly prescribed to diabetics to reduce postprandial hyperglycemia induced by the digestion of starch in the small intestine 3. The overall effect of inhibition is to reduce the flow of glucose from complex dietary carbohydrates into the bloodstream, diminishing the postprandial effect of starch consumption on blood glucose levels 4.
However, the leading glucosidase inhibitors, acarbose and miglitol, are often reported to produce diarrhea and other intestinal disturbances, with corresponding intestinal pain and flatulence 45. Randomized controlled trials with glucosidase inhibitors report these gastrointestinal side-effects as the most common reason for non-compliance and early subject withdrawal 6.
The consumption of plants or plant-based supplements may be a more acceptable source of glucosidase inhibitors due to low cost and relative safety, including a low incidence of serious gastrointestinal side-effects 7 — 9.
Rich in polyphenolic flavonoid compounds, extracts from grape seed and green tea have been of increasing interest due to their anti-diabetic properties 13 — Green and white teas are particularly abundant in catechins and catechin 3-gallates. The most abundant catechin 3-gallate in green and white tea, epigallocatechin gallate EGCGis attributed with providing many of the beneficial, anti-diabetic effects of tea consumption 1317 In contrast, grape seed extract contains not only catechins and catechin 3-gallates, but also oligomeric flavanols, called procyanidins 19 In addition, catechin constituents of these extracts were also tested for their ability to act as glucosidase inhibitors.
Louis, MO. Salt Lake City, UT. Catechins were quantified based on reference to purified standards, and expressed as total of extract weight Table 1. Oligomeric content of grape seed extract was determined after separation on a gel organic column Phenogel A; Phenomenex, Torrance, CA using a tetrahydrofuran mobile phase and absorbance at nm.
Oligomeric content tetramers and large compounds was expressed as a comparison to grape seed oligomeric proanthocyanidin reference standard USP Cat Phenolic composition was measured using a modified Folin-Ciocalteu assay and expressed in percentage of gallic acid equivalents GAE.
The final concentrations of extracts and catechins were between 0. DMSO concentrations ranged from 0. The linear rate of product formation during the initial 15 min of incubation was used to calculate enzyme activity. Control wells with only test compound, but no enzyme or substrate, were used to determine any background auto-fluorescence. Extracts and catechins were prepared as described above. All test compounds were prepared in DMSO as described above.All courses, faculty listings, and curricular and degree requirements described herein are subject to change or deletion without notice.
For course descriptions not found in the UC San Diego General Catalog —20please contact the department for more information. This seminar connects first-year students with the chemistry community peers, staff, faculty, and other researchers as they explore learning resources, study strategies, professional development, and current areas of active research. With an emphasis on academic and career planning, the series will feature guest lectures by UC San Diego faculty and staff, as well as industrial scientists and representatives from professional organizations such as the American Chemical Society ACS.
Offers less well-prepared science majors the fundamental skills necessary to succeed in CHEM 6. Emphasizes quantitative problems. Topics include nomenclature, stoichiometry, basic reactions, bonding, and the periodic table.
Restricted to freshmen and sophomores. First quarter of a three-quarter sequence intended for science and engineering majors.
Chemistry and Biochemistry
Topics include atomic theory, bonding, molecular geometry, stoichiometry, types of reactions, and thermochemistry. First quarter of a three-quarter honors sequence intended for well-prepared science and engineering majors. Topics include quantum mechanics, molecular orbital theory, and bonding. An understanding of nomenclature, stoichiometry, and other fundamentals is assumed. Students completing 6AH may not subsequently take 6A for credit.
Recommended: completion of a high school physics course strongly recommended. Second quarter of a three-quarter sequence intended for science and engineering majors. Topics include covalent bonding, gases, liquids, and solids, colligative properties, physical and chemical equilibria, acids and bases, solubility. Second quarter of a three-quarter honors sequence intended for well-prepared science and engineering majors.
Topics include colligative properties, bulk material properties, chemical equilibrium, acids and bases, and thermodynamics. Three hour lecture and one hour recitation. Students completing 6BH may not subsequently take 6B for credit. Third quarter of a three-quarter sequence intended for science and engineering majors.Oxidizing and reducing agents are key terms used in describing the reactants in redox reactions that transfer electrons between reactants to form products.
This page discusses what defines an oxidizing or reducing agent, how to determine an oxidizing and reducing agent in a chemical reaction, and the importance of this concept in real world applications. An oxidizing agentor oxidantgains electrons and is reduced in a chemical reaction.
Also known as the electron acceptor, the oxidizing agent is normally in one of its higher possible oxidation states because it will gain electrons and be reduced. Examples of oxidizing agents include halogens, potassium nitrate, and nitric acid. A reducing agent, or reductantloses electrons and is oxidized in a chemical reaction. A reducing agent is typically in one of its lower possible oxidation states, and is known as the electron donor.
A reducing agent is oxidized, because it loses electrons in the redox reaction. Examples of reducing agents include the earth metals, formic acid, and sulfite compounds.
To help eliminate confusion, there is a mnemonic device to help determine oxidizing and reducing agents. Oxidizing and reducing agents are important in industrial applications. They are used in processes such as purifying water, bleaching fabrics, and storing energy such as in batteries and gasoline. Oxidizing and reducing agents are especially crucial in biological processes such as metabolism and photosynthesis.
All combustion reactions are also examples of redox reactions. A combustion reaction occurs when a substance reacts with oxygen to create heat. One example is the combustion of octane, the principle component of gasoline:. Combustion reactions are a major source of energy for modern industry.
By looking at each element's oxidation state on the reactant side of a chemical equation compared with the same element's oxidation state on the product side, one can determine if the element is reduced or oxidized, and can therefore identify the oxidizing and reducing agents of a chemical reaction. Oxidizing and Reducing Agents An oxidizing agentor oxidantgains electrons and is reduced in a chemical reaction.
Definitions A reducing agent reduces other substances and loses electrons; therefore, its oxidation state increases.
An oxidizing agent oxidizes other substances and gains electrons; therefore, its oxidation state decreases. Table 1: Commons oxidizing and reducing agents Common oxidizing agents. Common reducing agents. Halogens they favor gaining an electron to obtain a noble gas configuration. Alkali metals they favor losing an electron to obtain a noble gas configuration. Oxidation States: -1 0.
Applications Oxidizing and reducing agents are important in industrial applications. Summary By looking at each element's oxidation state on the reactant side of a chemical equation compared with the same element's oxidation state on the product side, one can determine if the element is reduced or oxidized, and can therefore identify the oxidizing and reducing agents of a chemical reaction.
Reduced Oxidized. Is B the oxidizing or reducing agent? Which one is reduced and which one is oxidized? In a redox reaction, there must be an oxidizing agent and no reducing agent a reducing agent and no oxidizing agent a reducing agent and an oxidizing agent no reducing or oxidizing agent Which of the following is a strong reducing agent?
Which of the following is a strong oxidizing agent? Remember that gaining electrons means it is "reduced". Keep in mind that losing electrons means it is "oxidized". In this reaction, hydrogen loses one electron.The identity of an element is defined by its atomic number Z The number of protons in the nucleus of an atom of an element.
The atomic number is therefore different for each element. The known elements are arranged in order of increasing Z in the periodic table a chart of the chemical elements arranged in rows of increasing atomic number so that the elements in each column group have similar chemical properties Figure 1.
We will explain the rationale for the peculiar format of the periodic table later. The names of the elements are listed in the periodic table, along with their symbols, atomic numbers, and atomic masses. The chemistry of each element is determined by its number of protons and electrons.
In a neutral atom, the number of electrons equals the number of protons. Figure 1. The semimetals lie along a diagonal line separating the metals and nonmetals. In the third chapter we will discover why the table appears as it does. If you want to learn the names of the elements and how to pronounce them, there is nothing better than a song. Old timers perhaps your lecturer is the only one in the class will recognize this as a cover of Tom Lehrer's Song of the Elements.
Elements have also been named for their properties [such as radium Ra for its radioactivity], for the native country of the scientist s who discovered them [polonium Po for Poland], for eminent scientists [curium Cm for the Curies], for gods and goddesses [selenium Se for the Greek goddess of the moon, Selene], and for other poetic or historical reasons. Some of the symbols used for elements that have been known since antiquity are derived from historical names that are no longer in use; only the symbols remain to remind us of their origin.
Examples are Fe for iron, from the Latin ferrum ; Na for sodium, from the Latin natrium ; and W for tungsten, from the German wolfram. Examples are in Table 1. As you work through this text, you will encounter the names and symbols of the elements repeatedly, and much as you become familiar with characters in a play or a film, their names and symbols will become familiar.CHEM113L: Equilibrium Constant Post-lab Analysis
Table 1. Recall from Section 1. Unlike protons, the number of neutrons is not absolutely fixed for most elements. Atoms that have the same number of protonsand hence the same atomic number, but different numbers of neutrons are called isotopes.
All isotopes of an element have the same number of protons and electrons, which means they exhibit the same chemistry. The isotopes of an element differ only in their atomic mass, which is given by the mass number Athe sum of the numbers of protons and neutrons.
8 simple chemistry experiments that your kids can do at home
The element carbon C has an atomic number of 6, which means that all neutral carbon atoms contain 6 protons and 6 electrons. In a typical sample of carbon-containing material, In addition to 12 C, a typical sample of carbon contains 1.
The nucleus of 14 C is not stable, however, but undergoes a slow radioactive decay that is the basis of the carbon dating technique used in archaeology.
Many elements other than carbon have more than one stable isotope; tin, for example, has 10 isotopes. The properties of some common isotopes are in Table 1.
Sources of isotope data: G. Audi et al. Kotz and K.Covers basic concepts of chemistry along with the mathematics required for quantitative problem solving.
For students without high school chemistry or with limited mathematics background. Prerequisite: assessment of skills by taking the General Chemistry Placement Exam. Offered: AWS. Not for students majoring in biochemistry, chemistry, or engineering. Includes matter and energy, chemical nomenclature, chemical reactions, stoichiometry, modern atomic theory, chemical bonding.
Atomic nature of matter, quantum mechanics, ionic and covalent bonding, molecular geometry, stoichiometry, solution stoichiometry, kinetics, and gas laws. Includes laboratory.
Cannot be taken for credit if CHEM already taken. Offered: AWSpS. For science and engineering majors.
Stoichiometry, gas laws, atomic structure, quantum mechanics, general bonding, kinetics, gas-phase equilibria, acid-base equilibria, applications of aqueous equilibria. Offered: A.
Chemistry 125/126 - General Chemistry Laboratory 1
Prerequisite: minimum grade of 1. Thermodynamics, electrochemistry, bonding, liquids, solid and solutions, transition metals. Prerequisite: 2. Offered: W. Prerequisite: minimum grade of 2. Includes coordination complexes, geochemistry, and metallurgy.
Additional material on environmental applications of basic chemistry presented. Offered: Sp.