...Determining the Limiting Reactant and Percent Yield in a Precipitation Reaction Objectives: • Observe the reaction between solutions of sodium carbonate and calcium chloride. • Determine which of the reactants is the limiting reactant and which is the excess reactant. • Determine the theoretical mass of precipitate that should form. • Compare the actual mass with the theoretical mass of precipitate and calculate the percent yield. Materials: Balance 0.70 M sodium carbonate solution, Na2CO3(aq) Graduated cylinder 0.50 M calcium chloride solution, CaCl2(aq) Beaker (250 mL) Wash Bottle (distilled H2O) Filter paper Funnel Iron ring Ring stand Procedure: Part I: The Precipitation Reaction (Day 1) 1. Obtain two clean, dry 25 mL graduated cylinders and one 250 mL beaker. 2. In one of the graduated cylinders, measure 25 mL of the Na2CO3 solution. In the other graduated cylinder, measure 25 mL of the CaCl2 solution. Record these volumes in your data table. 3. Pour the contents of both graduated cylinders into the 250 mL beaker and observe the results. Record these qualitative observations in your observations table. Allow the contents of the beaker to sit undisturbed for approximately 5 minutes to see what happens to the suspended solid particles. Meanwhile, proceed to step 4. 4. Obtain a piece of filter paper and put your initials and your partner’s initials on it using a pencil. Measure and record the mass of the filter paper, then use...
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...chemistry, we use symbols to represent the various chemicals. Success in chemistry depends upon developing a strong familiarity with these basic symbols. For example, the symbol "C"represents an atom of carbon, and "H" represents an atom of hydrogen. To represent a molecule of table salt, sodium chloride, we would use the notation "NaCl", where "Na" represents sodium and "Cl" represents chlorine. We call chlorine "chloride" in this case because of its connection to sodium. You should have reviewed naming schemes, or nomenclature, in earlier readings. A chemical equation is an expression of a chemical process. For example: AgNO3(aq) + NaCl(aq) ---> AgCl(s) + NaNO3(aq) In this equation, AgNO3 is mixed with NaCl. The equation shows that the reactants (AgNO3 and NaCl) react through some process (--->) to form the products (AgCl and NaNO3). Since they undergo a chemical process, they are changed fundamentally. Often chemical equations are written showing the state that each substance is in. The (s) sign means that the compound is a solid. The (l) sign means the substance is a liquid. The (aq) sign stands for aqueous in water and means the compound is dissolved in water. Finally, the (g) sign means that the compound is a gas. Coefficients are used in all chemical equations to show the relative amounts of each substance present. This amount can represent either the relative number of molecules, or the relative number of moles (described below). If no coefficient is shown, a one (1)...
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...CHAPTER 3 MASS RELATIONSHIPS IN CHEMICAL REACTIONS This chapter reviews the mole concept, balancing chemical equations, and stoichiometry. The topics covered in this chapter are: • Atomic mass and average atomic mass • A vogadro’ s number, mole, and molar mass • Percent composition calculations • Empirical and molecular formula determinations • Chemical equations, amount of reactant and product calculations • Limiting reagents and reaction yield calculations Take Note: It is absolutely essential that you master the mole concept to do well on the quantitative aspects of AP Chemistry!! When solving quantitative problems on the Free Response section of the AP exam, supporting work must be shown to receive credit. Using dimensional analysis is a very powerful technique in solving problems. Be sure to report your answer to the correct number of significant figures (see Chapter 1 in this review book). Atomic mass and average atomic mass Atomic mass is the mass of an atom in atomic mass units (amu). One amu is defined as 1/12 of one C-12 atom. The C-12 isotope has a mass of exactly 12.000 amu. The C-12 isotope provides the relative scale for the masses of the other elements. Average atomic mass is the value reported on the periodic table, which takes into account the various isotopes of an element and their respective frequencies. To calculate the average atomic mass of an element, add up the different masses of the isotopes (using amu) multiplied by each isotope’s abundance...
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...Lab Report Marco Huerta Partner: Sami Mrestani Chem 12B – Organic Chemistry 11/07/11 Lazik Benzocaine Objective: To prepare a local anesthetic, Benzocaine, by the direct estherification of p-aminobenzoic acid with ethanol. Abstract: Over the years many new local anesthetics have been synthesized and tested. Though many have not come into general use, the search for the perfect local anesthetic is still under way. An interesting fact about these compounds is that they all share common feature (see general structure below). At one end of the molecule is an aromatic ring. At the other is a secondary or tertiary amine. These two ends are separated by a central chain of atoms usually one to four units long. The aromatic part is typically and ester of an aromatic acid which is important to the bodily detoxification of these compounds. In our experiment, we created a topical anesthetic, Benzocaine, by the direct estherification of p-aminobenzoic acid. This was accomplished by reaction with absolute ethanol catalyzed by concentrated sulfuric acid and later neutralized with a 10% sodium carbonate solution. Neutralization raised the pH of the overall reaction system to about 8 creating a precipitate of Benzocaine. Recrystallization of the crude product was performed to increase purity. Our...
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...Why do we keep a lab notebook? In the ‘real world’, you will be expected to record what you do and how you do it, with the data clearly identifiable. There are 2 reasons for this: • Any scientific experiment is only considered valid if it can be repeated by someone else using your notebook. • If you develop a new product or process, your notebook becomes a legal document that can be scrutinized in a court of law, especially in cases of patent infringement. In order to meet these requirements, certain conditions must be met: • Notebooks shall have bound pages, loose-leaf and spiral bound are not acceptable. • All pages must be numbered prior to use. This will show if any pages have been removed that contained data that might compromise interpretation of your conclusions. • All data shall be entered chronologically. Do not leave empty pages to insert information later. If you finish with a large expanse of blank page, put a line through it to show that it will not be used. • All notes are to be made in indelible pen – pencil will be penalized. If you make a mistake, just draw a single line through it, not a childish scribble to hide all traces! • All data will be recorded in your lab notebook at the moment it is generated. No notes shall be written on scraps of paper or memorized for later. Other notes about the lab notebook: All pre-lab and experimental work is hand-written in your lab notebook. Make...
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...reaction. When a neutralization reaction occurs, heat (q) is released to the surroundings, and the temperature of the surroundings rises. In aqueous acid-base neutralization reactions the surroundings are the solution itself, which is mainly composed of water. The amount of heat released by the reaction can be determined by measuring the temperature change of the solution during the reaction. At constant pressure, the heat released by a reaction is the reaction enthalpy (∆Hr). The units for reaction enthalpies are kJ mol-1; in reactions that don’t have a 1-to-1 ratio of all reactants and products, we need to specify per mol of which species. In this experiment, the heat released by each reaction will be used to determine the reaction enthalpy for each chemical reaction per mole of acid reacted. (Note that this may or may not be the same thing as “per mole of acid added;” you will need to think about limiting reagents.) During the experiments the temperature change that occurs in solution will be monitored using a temperature probe connected to data collecting software on a laptop computer. Any heat given off to the surroundings beyond the solution will be neglected because it is assumed a negligible amount of heat will be lost beyond the solution. The heat released by each reaction will be determined using the temperature change data collected (∆T),...
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...BIOL 3380 Name:_____________________________________ Circle Session: T-PM W-AM W-PM R-AM R-PM F-AM F-PM Experiment 9 – Pre-lab Homework Enzyme Kinetics of LDH This pre-lab homework assignment is due at the beginning of your lab session. You are provided with the following portion of a protocol: • Determine concentration of enzyme stock solution, if unknown, by taking an A280 nm reading of a 1:100 dilution (in water). Use a total volume of 1 ml in the cuvette. • Dilute some of the enzyme stock with buffer A to make a 4 mg/ml solution. • Serially dilute the 4 mg/ml solution with buffer A to make working solutions of 400 µg/ml and 40 µg/ml. • Prepare 30 µl of each working solution for every sample The PI of the lab gives you a tube of enzyme and tells you the following before disappearing into the office to write more grant proposals: ➢ There is 50 µl of enzyme stock solution. The enzyme is expensive to purify, so follow the protocol exactly, using as little of the stock solution as possible. ➢ The concentration of the stock solution is currently not known, but a 1 mg/ml concentration of the pure enzyme has an A280 nm of 2.0. ➢ You’ll be performing the assay on 12 samples. ➢ Make enough of each working solution so that you have at least 400 ul to work with when you do the assay (to cover any waste and/or inefficiencies in pippetting). Using the spectrophotometer to read the absorbance at 280 nm, you get...
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...average of 0.0664, the accepted value for the reaction was 2nd order. The calculated percent error was found to be 66.8% using the percent error equation shown in the appendix. The average order for the magnesium ribbon was expected to be 1st order, it was found to be 0.738. The percent error was calculated to be 26.8% for the order of magnesium in the reaction. The derivation of rate law using a pressure probe and Erlenmeyer flask was found to be a mediocre technique of finding rate law. Kinetics and rate laws are important because it influences the rate of food spoilage and the rate of degradation of common drugs.5 Since kinetics and rate laws are so important in everyday life, calculating rate law using the technique used in this lab would not be the most effect and precise way of finding...
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...[pic] Official TCC Course Syllabus |Discipline Prefix: CHM |Course Number: 111 |Course Title: College Chemistry I | | |Course Section: D04B | | |Credit Hours: 4 |Lecture Hours: 3 |Clinical Hours: |Lab Hours: 3 | |Contact Hours: 6 |Studio Hours: N/A |Semester: Fall | |Meeting Days/Time/Location: Fridays/1:30pm-4:20pm/Science Building | Instructor Information Name: Dr. Shahin Maaref Office Location: JD-30 Office Hours: TRF 9:00am-11:00am, TR 4:30pm-5:30pm & by appointment Contact Information: 822-7692 Blackboard site: http://learn.vccs.edu Instructor email address: smaaref@tcc.edu Course Information Course Description Explores the fundamental laws, theories, and mathematical concepts of chemistry. Designed primarily for science and engineering majors. Requires a strong background in mathematics. Part I of II. Prerequisites and/or Co-requisites Prequisites - None Corequisites – None It is recommended to have H.S. chemistry or CHM01 as prerequisites and MTH 03 or MTE 06 level or higher. ...
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...Chemistry Modern Analytical Chemistry David Harvey DePauw University Boston Burr Ridge, IL Dubuque, IA Madison, WI New York San Francisco St. Louis Bangkok Bogotá Caracas Lisbon London Madrid Mexico City Milan New Delhi Seoul Singapore Sydney Taipei Toronto McGraw-Hill Higher Education A Division of The McGraw-Hill Companies MODERN ANALYTICAL CHEMISTRY Copyright © 2000 by The McGraw-Hill Companies, Inc. All rights reserved. Printed in the United States of America. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a data base or retrieval system, without the prior written permission of the publisher. This book is printed on acid-free paper. 1 2 3 4 5 6 7 8 9 0 KGP/KGP 0 9 8 7 6 5 4 3 2 1 0 ISBN 0–07–237547–7 Vice president and editorial director: Kevin T. Kane Publisher: James M. Smith Sponsoring editor: Kent A. Peterson Editorial assistant: Jennifer L. Bensink Developmental editor: Shirley R. Oberbroeckling Senior marketing manager: Martin J. Lange Senior project manager: Jayne Klein Production supervisor: Laura Fuller Coordinator of freelance design: Michelle D. Whitaker Senior photo research coordinator: Lori Hancock Senior supplement coordinator: Audrey A. Reiter Compositor: Shepherd, Inc. Typeface: 10/12 Minion Printer: Quebecor Printing Book Group/Kingsport Freelance cover/interior designer: Elise Lansdon Cover image: © George Diebold/The...
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...Resume Guide for Teachers This packet is intended to serve as a starting point for creating or improving your teaching resume. Included in this packet are best practices that the Career Center have researched and found to be true. Information and sample resumes within this packet are not intended to be taken verbatim. Constructing a teaching resume is an art, not a science. Make your personal resume unique and stand out by making it represent you. The resources this packet highlights are available to all students; take advantage of the Career Center and the services it provides you. What to Expect Teaching Resume Aesthetics, Content & Editing…………..………………………..Page 3 Three necessary components of a great teaching resume are detailed Key Elements of a Successful Teacher Resume……………………………………...Page 4 Mandatory vs. optional elements in a successful teaching resume Poor Teaching Resume Example……………………………………………………..Page 5 Details common mistakes of a teaching resume Transferable Skills & Action Verbs…………………………………………………....Page 6 A comprehensive list of transferable skills and action verbs that have potential in a teaching resume Constructing a Proper Achievement Statement (bullet point)………………………Page 7 Creating a bullet point stress you out? Here is a fool proof way to construct a proper achievement statement. Buzz Words……………………………………………………………………………..Page 7 Answer the question, “What are buzz words and how should they be used in a resume” Teaching...
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...M UM B A I S I L I C O N VA L L E Y BANGALORE S I NG A P ORE M UM BA I -BK C NEW DELH I M UNI CH Intellectual Property Law in India December 2013 © Copyright 2013 Nishith Desai Associates www.nishithdesai.com Intellectual Property Law in India About NDA Nishith Desai Associates (NDA) is a research based international law firm with offices in Mumbai, Bangalore, Silicon Valley, Singapore, New Delhi, Munich. We specialize in strategic legal, regulatory and tax advice coupled with industry expertise in an integrated manner. We focus on niche areas in which we provide significant value and are invariably involved in select highly complex, innovative transactions. Our key clients include marquee repeat Fortune 500 clientele. Core practice areas include International Tax, International Tax Litigation, Litigation & Dispute Resolution, Fund Formation, Fund Investments, Capital Markets, Employment and HR, Intellectual Property, Corporate & Securities Law, Competition Law, Mergers & Acquisitions, JVs & Restructuring, General Commercial Law and Succession and Estate Planning. Our specialized industry niches include financial services, IT and telecom, education, pharma and life sciences, media and entertainment, gaming, real estate and infrastructure. IFLR1000 has ranked Nishith Desai Associates in Tier 1 for Private Equity (2014). Chambers & Partners has ranked us as # 1 for Tax, TMT and Private Equity (2013). Legal Era, a prestigious Legal Media Group...
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...PROJECT REPORT FOR AWARDING OF CERTIFICATE ON COMPLETION OF SUMMER INPLANT TRAINING (1st JUNE- 22nd JULY 2011) AT IOCL Gujarat Refinery (Vadodara) SUBMITTED BY: SHREYASH GUPTA Integ.Btech(APE)+MBA(O&G Management) University of Petroleum and Energy Studies,Dehradun PREFACE Though it has been said that best friend a man can ever get is a book but we at this juncture realize that only books cannot give all the information a person seeks. When any student is unable to understand a particular topic, he is advised to imagine the whole matter and then try to understand it. Normally, this method succeeds. But in engineering stream considering the study of wide range of process and equipments involved in it, it is hard to understand the unit operations and processes just through books or even with imagination .Unless one happens to see the process, equipments, he is like a soldier who knows to fire the gun ,but is yet to face a war. Industrial training is one of the most vital part of a syllabus of chemical engineering, which not only teaches one the industrial unit operations, equipments and other technical aspects, but also teaches discipline, interaction with various people irrespective of their posts, the importance of teamwork, etc. This report contains a brief introduction to GUJRAT REFINERY and knowledge gathered about various units in refinery during the training. ACKNOWLEDGEMENT I would like to express...
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...1 UNIT 1 Living Things and Their Environment DRAFT April 29, 2014 Photo Credit: http://www.flyingfourchette.com/2013/05/25/around-ubud/ 2 UNIT 1: Living Things and Their Environment Introduction At this point, students have already learned in Grade 8 how the body breaks down food into forms that can be absorbed through the digestive system and then transported to each cell, which was on the other hand discussed in Grade 7 to be the basic unit of life. The learners have also discovered that cells divide to produce new cells by mitosis and meiosis. They have understood that meiosis is an early step in sexual reproduction that leads to variation. Students have been introduced to genetics to be able to appreciate evolutionary differences among species. Learners have also found out that biodiversity is the collective variety of species living in an ecosystem, and by studying the ecosystem; they have come across the various cycling of materials and energy transformation. DRAFT April 29, 2014 All modules in Grade 9 Unit 1-Living Things and Their Environment present student-centered activities that will allow the learners to discover and develop concepts that they may consider useful to their everyday life. At the end of each lesson, key concepts are provided for the students to grasp ideas and information that they will remember even after they have left school. Instructional activities are designed to build up the students’ knowledge, understanding, skills, and ability to transfer...
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...NOTE: This PDF document has a handy set of “bookmarks” for it, which are accessible by pressing the Bookmarks tab on the left side of this window. ***************************************************** We are the last. The last generation to be unaugmented. The last generation to be intellectually alone. The last generation to be limited by our bodies. We are the first. The first generation to be augmented. The first generation to be intellectually together. The first generation to be limited only by our imaginations. We stand both before and after, balancing on the razor edge of the Event Horizon of the Singularity. That this sublime juxtapositional tautology has gone unnoticed until now is itself remarkable. We're so exquisitely privileged to be living in this time, to be born right on the precipice of the greatest paradigm shift in human history, the only thing that approaches the importance of that reality is finding like minds that realize the same, and being able to make some connection with them. If these books have influenced you the same way that they have us, we invite your contact at the email addresses listed below. Enjoy, Michael Beight, piman_314@yahoo.com Steven Reddell, cronyx@gmail.com Here are some new links that we’ve found interesting: KurzweilAI.net News articles, essays, and discussion on the latest topics in technology and accelerating intelligence. SingInst.org The Singularity Institute for Artificial Intelligence: think tank devoted to increasing...
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