3/22/2012 ARYL HALIDES 2. displacement reactions of diazonium salts ARYL HALIDES General formula: Ar–X where X = F‚ Cl‚ Br or I Examples Structure: C-X bonds are shorter and stronger Bond C-Cl C-Br Ar-X 1.69 A° 1.86 A° R-X 1.77 1.91 Dipole moments are unusually small. Bond C-Cl Preparation: 1. electrophilic aromatic substitution – useful only if one product is obtained C-Br Ar-X 1.7 D 1.7 D R-X 2.10 D 2.15 D Dipole moments may cancel out depending on the geometry of the
Premium Electrophilic aromatic substitution Organic reaction Solvent
as grafting monomer and glycidyl methacrylate (GMA) as crosslinker. Properties such as dimensional stability‚ water absorption‚ hardness‚ tensile strength‚ flexural strength‚ etc of the impregnated wood have been checked and found to be improved by incorporation of GMA as the crosslinker with styrene. The polymerimpregnated wood has also been characterized by FTIR spectroscopy and DSC. Keywords. 1. Wood; composite; crosslinker; polymers; styrene–glycidyl methacrylate. Introduction
Premium Polymer Strength of materials Wood
absolute zero - a theoretical condition concerning a system at zero Kelvin where asystem does not emit or absorb energy (all atoms are at rest) accuracy - how close a value is to the actual or true value; also see precision acid - a compound that‚ when dissolved in water‚ gives a pH of less than 7.0 or a compound that donates a hydrogen ion acid anhydride - a compound with two acyl groups bound to a single oxygen atom acid dissociation constant - an equilibrium constant for the dissociation of
Free Atom
solution was used to adjust pH of the bath. In order to obtain good quality thin films‚ time‚ deposition temperature and pH of the solution were optimized and they are found to be 1 hour‚ 50°C and 10 respectively. Characterization included XRD and UV spectroscopy and electrical conductivity. The results are discussed and interpreted. Keywords: Pb(S‚Se)‚ thin film‚ chemical bath deposition technique. 1. Introduction: Semiconducting lead salt alloys PbxSn1-xSe‚ PbxSn1-xTe and PbSxSe 1-x have attracted
Premium Chemistry Semiconductor
Clinically‚ non-steroidal anti-inflammatory drugs (NSAIDs) are the most frequently prescribed class of drugs for inflammatory disorders (1). Lornoxicam is a novel NSAID drug. It has an equipotent COX isoenzyme inhibitory effect and subsequently reduces the production of prostaglandins‚ thromboxane‚ and leukotrienes (2). It is prescribed for mild to moderate pain and inflammation in osteoarthritis and rheumatoid arthritis (3). It is prescribed for the treatment of osteoarthritis due to its analgesic
Premium Stomach Pharmacology
CHAPTER 3 Studies on Mn (II)‚ Co (II)‚ Ni(II)‚Cu(II)‚Zn(II) and Cd(II) Complexes of Dimedone bis Semicarbazone (H2DSC) During the past few decades‚ major developments have been achieved in the research of coordination compounds with special emphasis on metal complexes of Schiff bases containing nitrogen and oxygen donors 1-5 . This may be due to their stability‚ biological activity5-6and potential applications in many fields 9-10. Biological activity of complexes derived from semicarbazide has
Premium Protein DNA Chemistry
Liquid CO2 Extraction of D-Limonene This convenient‚ effective and inexpensive liquid CO2-based extraction of a natural product (D-limonene) provides an engaging example of natural products extraction using an alternative solvent (liquefied CO2). Because the procedure can be carried out in a polypropylene centrifuge tube and uses crushed dry ice as its CO2 source‚ it provides an inexpensive alternative to the equipment-intensive extraction with supercritical CO2. A short video clip is available
Premium Solvent Solubility Solution
1-propanol and 2-pentanol with NaBr in H2SO4‚ in which the H2O acts as the leaving group and Br as the attaching nucleophile (1). After the reaction has taken place through reflux and distillation‚ the product is able to be examined through NMR and IR spectroscopy analysis. Finally‚ these graphs will help in determining the products of each reaction and the type of mechanism used. SN1: SN2: Mechanism of 1-propanol: Mechanism of 2-pentanol: Table of Reagents Compound | Molecular Weight |
Premium Distillation Alcohol Ethanol
Department of Chemistry University of Kentucky EXPERIMENT 5 Molecular Absorption Spectroscopy: Determination of Iron With 1‚10-Phenanthroline UNKNOWN Submit a clean‚ labeled 100-mL volumetric flask to the instructor so that your unknown iron solution can be issued. Your name‚ section number‚ and locker number should be written legibly on this flask. The flask does not need to be dry on the inside‚ but needs to have been rinsed with distilled water after it has been washed. The flask
Free Chemistry Concentration Analytical chemistry
Tessa Landauer Chemistry 0340 Qualitative Analysis Shaopeng Zhang January 26‚ 2015 I submit this laboratory report as an original document. I assert that all ideas and discussion of data contained herein is my own work unless otherwise referenced. Tessa Landauer Abstract The goal of the experiment was to isolate and purify the unknown D liquid and solid by using its acidic and basic characteristics in a chemically active extraction then to identify the unknowns by analyzing the physical properties
Premium Solvent Temperature Chemistry