foam (furniture padding) http://clinmedres.org/content/1/4/281.short. Similar in structure to polychlorinated biphenyls (PCBs)‚ PBDEs resist degradation in the environment. PBDEs were typically produced commercially at three different levels of bromination; nominally penta-‚ octa- and deca-BDE. The deca-PBDE formulation made up 83.3% of the 2001 PBDE global market demand‚ followed by penta- 11.1%‚ and octa- 5.6 %( LaA Guardia et al 2006). While PBDE’s are shown to be harmful in that they are bioaccumulative
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Revision Notes IGCSE Chemistry Triple Award Revision Guide Topic Introduction to chemistry Atomic Structure Structure and Bonding – Ionic Bonding Structure and Bonding – Covalent and Metallic Bonding Organic Chemistry - Alkanes Organic Chemistry – Alkenes / Addition Polymerisation Organic Chemistry – Alcohols / Condensation Polymerisation Calculations Periodic Table Reactivity Series and Metal Extraction Electrolysis Energetics Acids‚ Bases‚ Salts and Neutralisation Preparing and Analysing Salts Rates
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Vegetative reproduction (vegetative propagation‚ vegetative multiplication‚ vegetative cloning) is a form of asexual reproduction in plants. It is a process by which new individuals arise without production of seeds or spores. It can occur naturally or be induced by horticulturists. Although most plants normally reproduce sexually‚ many have the ability for vegetative propagation‚ or can be vegetatively propagated if small pieces are subjected to chemical (hormonal) treatments. This is because meristematic
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29) The structural formulas are given for these cis or trans alkenes. (a) trans-1‚2-dichloropropane (b) cis-2-pentene (c) cis-3-hexene (d) trans-2-hexene Write the structural formula for: (a) cis-1‚2-dichloropropene (b) trans-2-pentene (c) trans-3-hexene (d) cis-2-hexene 30) In each case‚ tell whether cis and trans exist. If they do‚ write the structural formulas for two isomers and label each cis or trans‚ (a) Br2CH2 : No (b) CH3CH2CH=CHCH2CH3: Yes (c) CH3CH=CHCH3:
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Liceo de Cagayan University COLLEGE OF MEDICAL LABORATORY SCIENCE Rodolfo N. Pelaez Boulevard‚ Kauswagan‚ Cagayan de Oro City An Organic Chemistry Project About Saturated and Unsaturated Fats in Vegetable Oils‚ Margarines‚ and Peanut Butters Submitted by : Zedrik O. Ortiz Submitted to : Dr. Luzviminda H. Saliga DEFINITION OF TERMS Saturated fat is a fatty acid that consists of triglycerides containing only saturated fatty acids. Saturated fatty acids have no double bonds between the
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β-unsaturated ketone such as the product in this experiment: trans-p-anisalacetophenone1. The major product of an aldol condensation is usually observed as a trans product as it provides less steric hindrance due to the substituents on each side of the alkene being placed farther apart1. 2‚4-dinitrophenylhydrazine is also used in this experiment to indicate the presence of a ketone. When hydrazine is reacted with a ketone in acidic conditions it produces 2‚4-dinitrophenylhydrazone which is a bright red
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triphenylmethanol using through Gridnard reaction 2. To study the operations of anhydrous reaction‚ water vapor distillation. Principles Alcohol is widely used in organic chemistry‚ not only as solute but also as intermediate to synthesize halide‚ alkene‚ ether‚ aldehyde and ketone etc. In laboratory‚ an important method of synthesizing alcohol is though the addition reaction of Gridnard reagent and carbonyl compound‚ whereas aldehyde is the most reactive and then to ketone or ester. Primary alcohol
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water into the boiling tube containing the gascous products. The brown colour of bromine water disappeared immediately. Why? The products of cracking contained unsaturated (hydrocarbons) / alkenes / C=C / ethane / reasonable name of alkene‚ which decolourised the bromine water immediately by addition reaction (2) (II) The student then dropped more bromine water into the boiling tube until the brown colour of the bromine water persisted. After about 10 minutes
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mass spec can be seen in figure 6. According to the experimental IR spectroscopy for the E isomer of phenylcinnamic acid the peaks of the wavenumber were at 2952‚ 2518 1672 and 1426 cm-1. The peak at 2952 presents the double bond CH stretch for the alkene carbon. The peak at 2518 presents the carboxylic acid –OH peak. The peak at 1672 could present the carbonyl group. The aromatic ring peaks are around 1600 and 1426-1492. Different values could be seen for the z isomer. The wavenumbers for the IR
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H B621/02 GENERAL CERTIFICATE OF SECONDARY EDUCATION GATEWAY SCIENCE SCIENCE B UNIT 1: Modules B1 C1 P1 (Higher Tier) TUESDAY 15 JANUARY 2008 Afternoon Time: 1 hour *CUP/T45720* Candidates answer on the question paper. Additional materials (enclosed): None Calculators may be used. Additional materials: Pencil Ruler (cm/mm) INSTRUCTIONS TO CANDIDATES • • • • • • • Write your name in capital letters‚ your Centre Number and Candidate Number in the boxes above. Use blue or black ink. Pencil may
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