Introduction Extraction is a purification technique used in organic chemistry to separate compounds from a mixture of two or more compounds. There are three different extraction techniques: liquid-liquid extraction‚ solid-liquid extraction and chemically active extraction. All three types of extraction follow the same principle. Organic molecules dissolve in organic solvents and polar molecules dissolve in aqueous solvents. This phenomenon is observed because of the intermolecular forces between
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EXPERIMENT 2 ACID DISSOCIATION CONSTANT OF AN INDICATOR DYE OBJECTIVES Using spectrophotometric method: determine the wavelengths at which the acid and base forms of the dye in aqueous medium exhibit maximum absorption; determine the molar absorptivities of the acid and base forms of the dye and estimate an unknown concentration of the dye in solution using the Beer-Lambert’s Law; and determine the acid dissociation constant of the indicator dye. THEORY The absorption or reflection of
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Mixture Melting Points Abstraction Determining the melting point is very significant in order to identify an unknown. In this experiment‚ measuring the melting point was done by using melting point apparatus. The melting point of the unknown sample #10 was 111.5˚C. There were two possible compounds which were dibenzoyl ethylene and o-Toluic acid because their melting points were 111.2˚C and 109.8˚C when each compound was mixed with the unknown. Therefore‚ the unknown #10 was dibenzoyl ethylene
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Mabel M. Kimble September 21‚ 2014 Chemistry 234 Recrystallization of Benzoic Acid ABSTRACT The recrystallization of Benzoic Acid was performed to fully master the ability to purify a solid compound. This form of purification technique is especially important in chemical identification‚ where the melting point of the compound is taken to confirm its purity. In order to perform recrystallization a solubility test much be completed. Four solvents (95% Ethanol‚ Petroleum Ether‚ Acetone and distilled
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Great Depression From Wikipedia‚ the free encyclopedia {draw:frame} Dorothea Lange’s Migrant Mother depicts destitute pea pickers in California‚ centering on Florence Owens Thompson‚ age 32‚ a mother of seven children‚ in Nipomo‚ California‚ March 1936. The Great Depression was a severe worldwide economic depression) in the decade preceding World War II. The timing of the Great Depression varied across nations‚ but in most countries it started in about 1929 and lasted until the late 1930s
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Causes and effects of the Great Depression in The United States Name: Qicai Li Course: ECO 258 Professor: Dr. Yasser Fahmy Date: Dec. 8‚ 2011 Word count: 2050 Abstract This paper discusses and analyzes the causes and effects of the Great Depression which happened in the United States during 1929 to late 1930s or early 1940s. The causes of the Great Depression are several‚ for example‚ the drastic decline in the quantity of money in industrial economies and the drops of the price on agricultural
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Aspirin analysis Introduction Aspirin‚ which is also known as acetylsalicylic acid. C9H8O4 is the chemical format for Asprin. The chemical structure of aspirin: Aspirin is anti-inflammatory. Aspirin is prepared by chemical synthesis from salicylic acid‚ by acetylation with acetic anhydride. The fact that it is an acid allows us to quantify the amount of aspirin in a solution. We would do this by by using an acid-base titration. Sodium hydroxide (NaOH) will be used In this experiment as the
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9.1 Manufacture of Sulphuric Acid 1. State uses of sulphuric acid in daily life. - lead acid batteries in automobiles and for home use - extraction of elements from ores - manufacturing of fertilizers 2.The following shows an incomplete flow chart of the Contact process. a) b)Chemical equation A. B. C. D. 3. Briefly explain the sources of sulphuric dioxide gas in atmosphere. -Sulphur dioxide is produced mainly from the combustion of fossil fuels
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Major depressive disorder (MDD) (also known as clinical depression‚ major depression‚ unipolar depression‚ or unipolar disorder; or asrecurrent depression in the case of repeated episodes) is a mental disorderﾧ characterized by a pervasive and persistent low moodﾧ that is accompanied by low self-esteemﾧ and by a loss of interest or pleasureﾧ in normally enjoyable activities. This cluster of symptoms (syndromeﾧ) was named‚ described and classified as one of the mood disordersﾧ in the 1980 edition
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Types of Depression Depression is now considered as the most common mental illness. As of September 20‚ 2012‚ the Centers for Disease Control (CDC) reported that about 9 percent of Americans are experiencing depression and 90 percent of suicidal reports are commonly caused by depression. The brain has a certain chemicals that work to keep your moods balanced. When your brain is not generating enough of these chemicals‚ there’s a tendency for you to become depressed. Depression is commonly referred
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