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    Pharmacognosy is the study of drugs of natural origin. The term comes from two Greek words: "pharmakon" meaning drug or medicine‚ and "gnosis" meaning knowledge. The American Society of Pharmacognosy defines pharmacognosy as "the study of the physical‚ chemical‚ biochemical and biological properties of drugs‚ drug substances or potential drugs or drug substances of natural origin as well as the search for new drugs from natural sources". Plant preparations are said to be medicinal or herbal when they

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    Atoms‚ Airs‚ and Chemical Bonding Rich McConnell‚ CH-201 Grantham University Atoms‚ Airs‚ and Chemical Bonding 1. Alcohol in our digestive system reacts with oxygen gas to form carbon dioxide and water.  How many grams of carbon dioxide are released if a 10.00 g alcohol sample reacts with 20.85 g of oxygen gas and produces 11.77 g of water? Answer: 19.08g CO2 2. Using the periodic table‚ fill in the missing information in the following table: Protons Neutrons Electrons Isotope Symbol 27  32  27 

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    Determining the Chemical Formula of a Hydrate Chemistry 11 3/5/2013 Purpose: To determine the percent by mass of water in a hydrate of copper (II) sulfate hydrate.  Hypothesis: I hypothesize that when the solution is heated the hydrate will convert to an anhydrous ionic compound. Then the percentage composition will be determined by weighing the mass of the white crystals. Materials: 400ml beaker‚ hot plate‚ tongs‚ scoopula‚ electronic balance‚ glass rod‚ hot pad‚ and 4g of hydrated

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    Mahlaqua Imran Chemical and Physical Changes Lab 09/09/13 I. Purpose: Identify the different changes as a physical change or a chemical change.  II. Safety: You may need safety goggles and gloves.  III. Pre-lab questions:  1. Identify the following as either chemical or physical changes:  a. Striking a match Chemical b. Food spoiling  Chemical c. Breaking a glass  Physical d. Mowing the grass  Physical

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    Bonds is something that retains and holds on together with one another. There are three major chemical bonds and they are‚ Ionic‚ Covalent‚ and Hydrogen bonds. An example of a covalent bond would be SCl^2 which is Sulfur dichloride. SCl^2 is a covalent bond because since they are close to each other in valence electrons‚ they have almost full outer shells so they share electrons with one another. A good example is table salt NaCl‚ because they are on opposite sides of the periodic table therefore

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    Calculations CALCULATION IN ORDER TO FIND THE PERCENTAGE OF VITAMIN C Chemical reaction: C6H8O6 + I2→ 2I + C6H6O6 Ascorbic Acid: C6H8O6 Relative formula mass of C6H8O6= (12.01076) + (1.007948) + (15.99946)= 176.12412 g/mol Convert Iodine lost from mL to dm-3 = Iodine lost in mL1000= Iodine lost in dm-3 Convert Iodine lost (dm-3) to moles (n) by multiplying it with the concentration of Iodine used: n=0.005 Iodine lost in dm-3= mol of C6H8O6 Find the mass (g) of C6H8O6 in 50 mL by using this

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    CHEMICAL KINETICS RESULTS AND DISCUSSION The balanced equation of the reaction between sodium thiosulfate and Hydrochloric acid is: S2O32- (aq) + 2 H+ (aq) SO2 (g) + S (s) +H2O (l) Using beakers with the same diameter was very important in conducting the experiment. If different sizes were used‚ the visibility of the “x” on the paper beneath the beaker could disappear from view too early or too late than the hypothetical time depending on the depth of the solution. It was also significant

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    Chemical Equilibrium ------------------------------------------------- ------------------------------------------------- RESULTS AND DISCUSSION A. Iron-Silver Equilibrium In studying equilibrium between iron and silver‚ 0.10 M FeSO4 and 0.10 M AgNO3 were used. The balanced equation for the reaction is: FeSO4 (aq) + 2 AgNO3 (aq) ↔ Fe(NO3)2 (aq) + Ag2SO4 (s) It has a net equation of: Fe2+(aq) + Ag+(aq) ↔ Fe3+(aq) + Ag(s) This part of the experiment

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    Name: Jayanti Magar Title: Observations of Chemical Changes Date: 02/11/015 Pre Lab Questions: Use what you learned in this lab to answer the following questions. A. Suppose a household product label says it contains sodium hydrogen carbonate (sodium bicarbonate). How would you test this material for the presence of sodium bicarbonate? I would add hydrochloric acid (HCl) with carbon dioxide with NaHCO3‚ and it should bubble and form gas. B. You know what color phenolphthalein and bromothymol

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    Chemical and Physical Changes in Matter Purpose: The purpose is to observe chemical and physical changes and to identify each. Procedure: Do experiments 1-8 as directed by the handout. Data and Results: Experiment | Observations | Type of Change | Supporting Evidence | 1 | -After a few seconds‚ yellow smoke was produced-Wood splinters are becoming black-Bottom part of test tube has black color on the sides-Some woods splinters have been burned to ash-Middle of test tube has yellow

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