CHAPTER 15 the Laboratory
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Experiment 5: Molar Volume of a Gas (Mg + Hcl)
1 CHEM 30A EXPERIMENT 5: MOLAR VOLUME OF A GAS (MG + HCL) Learning Outcomes Upon completion of this lab, the student will be able to: 1) Demonstrate a single replacement reaction. 2) Calculate the molar volume of a gas at STP using experimental data. 3) Calculate the molar mass of a metal using experimental data. Introduction Metals that are above hydrogen in the activity series will displace hydrogen from an acid and produce hydrogen gas. Magnesium is an example of a metal that is more active than hydrogen in the activity series. The reaction between magnesium metal and aqueous hydrochloric acid is an example of a single replacement reaction (a type of redox reaction). The chemical equation for this reaction is shown below: Mg(s) + 2HCl(aq) è MgCl2(aq) + H2(g) Equation 1 When the reaction between the metal and the acid is conducted in a eudiometer, the volume of the hydrogen gas produced can be easily determined. In the experiment described below magnesium metal will be reacted with an excess of hydrochloric acid and the volume of hydrogen gas produced at the experimental conditions will be determined. According to Avogadro’s law, the volume of one mole of any gas at Standard Temperature and Pressure (STP = 273 K and 1 atm) is 22.4 L. Two important Gas Laws are required in order to convert the experimentally determined volume of hydrogen gas to that at STP. 1. Dalton’s law of partial pressures. 2. Combined gas law. Dalton’s Law of Partial Pressures According to Dalton’s law of partial pressures in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases. -
22 Bull. Hist. Chem. 8 (1990)
22 Bull. Hist. Chem. 8 (1990) 15 nntn Cn r fr l 4 0 tllOt f th r h npntd nrpt ltd n th brr f th trl St f nnlvn n thr prt nd ntn ntl 1 At 1791 1 frn 7 p 17 AS nntn t h 3 At 179 brr Cpn f hldlph 8Gztt f th Untd Stt Wdnd 3 l 1793 h ntr nnnnt rprdd n W Ml "njn h Cht"Ch 1953 37-77 h pn pr dtd 1 l 179 nd nd b Gr Whntn th frt ptnt d n th Untd Stt S M ntr h rt US tnt" Ar rt Invnt hn 199 6(2 1- 19 ttrfld ttr fnjn h Arn hl- phl St l rntn 1951 pp 7 9 20h drl Gztt 1793 (20 Sptbr Qtd n Ml rfrn 1 1 W Ml rfrn 1 pp 7-75 William D. Williams is Professor of Chemistry at Harding r brt tr University, Searcy, Al? 72143. He collects and studies early American chemistry texts. Wyndham D. Miles. 24 Walker their British cultural heritage. To do this, they turned to the Avenue, Gaithersburg, MD 20877, is winner of the 1971 schools (3). This might explain why the Virginia assembly Dexter Award and is currently in the process of completing the took time in May, 1780 - during a period when their highest second volume of his biographical dictionary. "American priority was the threat of British invasion following the fall of Chemists and Chemical Engineers". Charleston - to charter the establishment of Transylvania Seminary, which would serve as a spearhead of learning in the wilderness (1). -
Determination of Calcium Metal in Calcium Cored Wire
Asian Journal of Chemistry; Vol. 25, No. 17 (2013), 9439-9441 http://dx.doi.org/10.14233/ajchem.2013.15017 Determination of Calcium Metal in Calcium Cored Wire 1,* 1 2 1 1 HUI DONG QIU , MEI HAN , BO ZHAO , GANG XU and WEI XIONG 1Department of Chemistry and Chemical Technology, Chong Qing University of Science and Technology, Chongqing 401331, P.R. China 2Shang Hai Entry-Exit Inspection and Quarantine Bureau, P.R. China *Corresponding author: Tel: +86 23 65023763; E-mail: [email protected] (Received: 24 December 2012; Accepted: 1 October 2013) AJC-14200 The calcium analysis method in cored wire products is mainly measuring the total calcium content, including calcium oxide and calcium carbonate. According to the chemical composition of calcium cored wire and the chemical property of the active calcium in it, the gas volumetric method has been established for the determination of calcium content in calcium cored wire and a set of analysis device is also designed. Sampling in the air directly, intercepting the inner filling material of samples, reacting with water for 10 min, using standard comparison method and then the accurate calcium content can be available. The recovery rate of the experimental method was 93-100 %, the standard deviation is less than 0.4 %. The method is suitable for the determination the calcium in the calcium cored wire and containing active calcium fractions. Key Words: Calcium cored wire, Active calcium, Gas volumetric method. INTRODUCTION various state of the calcium. However, because the sample is heterogeneous and the amount of the sample for instrumental 1-4 The calcium cored wire is used to purify the molten analysis is small, thus such sampling can not estimate charac- steel, modify the form of inclusions, improve the casting and teristics of the whole ones accurately, so there are flaws to use mechanical properties of the steel and also reduce the cost of the instrumental analysis to determine the calcium metal in steel. -
XXIX. on the Magnetic Susceptibilities of Hydrogen and Some Other Gases
Philosophical Magazine Series 6 ISSN: 1941-5982 (Print) 1941-5990 (Online) Journal homepage: http://www.tandfonline.com/loi/tphm17 XXIX. On the magnetic susceptibilities of hydrogen and some other gases Také Soné To cite this article: Také Soné (1920) XXIX. On the magnetic susceptibilities of hydrogen and some other gases , Philosophical Magazine Series 6, 39:231, 305-350, DOI: 10.1080/14786440308636042 To link to this article: http://dx.doi.org/10.1080/14786440308636042 Published online: 08 Apr 2009. Submit your article to this journal Article views: 6 View related articles Citing articles: 16 View citing articles Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=6phm20 Download by: [RMIT University Library] Date: 20 June 2016, At: 12:34 E 3o5 XXIX. On the MAgnetic Susceptibilities of llydrogen uud some otl~er Gases. /33/TAK~; S0~; *. INDEX TO SECTIONS. 1. INTRODUCTION. ~O. METI~OD OF 5LEASUREMENT. o. APPARATUS :FOR }IEASU14EIMF~NT. (a) Magnetic bMance. (b) Compressor and measuring tube. 4. PIt0CEDUI{E :FOR BIEASUREMENTS. (a) Adjustment of the measuring tube. (b) Determination of the mass. (c) Method of filling the measuring tube with gas. (d) Electromagnet. (e} Method of experiments. 5. Ain. 6. OXYGEN. ~. CARBON DIOXIDE. 8. NITROGEN. 9. ItYDI~0G~N. (a) Preparation of pure hydrogen gas. (b) Fillin~ the measuring tube with the gas. (e) YCesults el'magnetic measurement. (d} Purity of the hydrogen gas. 10. CONCLUDING REMARKS. wi. INTRODUCTION. N the electron theory of magnetism, it is assumed that I the magnetism is duo to electrons revolving about the positive nucleus in the atom; and hence the electronic structure of the atom has a very important bearing on its magnetic properties. -
A Study of Form and Content for a Laboratory Manual to Be Used by Students in General Chemistry Laboratory
Brigham Young University BYU ScholarsArchive Theses and Dissertations 1946-01-01 A study of form and content for a laboratory manual to be used by students in general chemistry laboratory Berne P. Broadbent Brigham Young University - Provo Follow this and additional works at: https://scholarsarchive.byu.edu/etd BYU ScholarsArchive Citation Broadbent, Berne P., "A study of form and content for a laboratory manual to be used by students in general chemistry laboratory" (1946). Theses and Dissertations. 8176. https://scholarsarchive.byu.edu/etd/8176 This Thesis is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. ?_(j;, . , i. ~ ~ (12 ' -8?5: 11% -· • A STUDY OF FOFM CONTENTFOR A LABORATORY -\ .AND MANUALTO BE USED BY STUDENTSIN GENERALCEEi/IISTRY LABORATORY' A THESIS SUBMITTEDTO \ THE DEPAR'.I3\t1Ell."'T OF CHEMISTRY OF ··! BRIGHAMYOUNG UNIVERSITY,. IN PARTIALFULFII.lllENT OF THEREQ,UIREMENTS·FOR THE DEGREE OF MASTEROF SCIENCE ... .,; . •·' .. ...• • .• . • "f ... ·.. .. ,. ·: :. !./:.•:-.:.lo>•.-,:... ... ... ..........• • • • p ,.. .,• • • ...• • . ~. ••,,. ................. :... ~•••,,.c • ..............• • • • • • .. f" ·~•-~-·"••• • • • ... • .., : :·.•··•:'"'•••:'"',. ·.-··.::· 147141 BY BERNEP. BROADBENT . " 1946 .,_ - ii \ ., This Thesis by Berne P.- Broadbent is accepted in 1ts P:esent form by the Departm·ent of Chem�stry as satisfying the Thesis requirement.for the degree of .J Master of Science • ,• . - .} .. iii PREF.ACE The constantly broadening field assigned to general chemistry demands that material be carefully selected and that ever increasing attention be given to preparing this material and presenting it_ to the student.- The following study was made to develop a laboratory manual that would increase the effectiveness of laboratory work. -
Inquiry-Based Laboratory Work in Chemistry
INQUIRY-BASED LABORATORY WORK IN CHEMISTRY TEACHER’S GUIDE Derek Cheung Department of Curriculum and Instruction The Chinese University of Hong Kong Inquiry-based Laboratory Work in Chemistry: Teacher’s Guide / Derek Cheung Copyright © 2006 by Quality Education Fund, Hong Kong All rights reserved. Published by the Department of Curriculum and Instruction, The Chinese University of Hong Kong. No part of this book may be reproduced in any manner whatsoever without written permission, except in the case of use as instructional material in a school by a teacher. Note: The material in this teacher’s guide is for information only. No matter which inquiry-based lab activity teachers choose to try out, they should always conduct risks assessment in advance and highlight safety awareness before the lab begins. While every effort has been made in the preparation of this teacher’s guide to assure its accuracy, the Chinese University of Hong Kong and Quality Education Fund assume no liability resulting from errors or omissions in this teacher’s guide. In no event will the Chinese University of Hong Kong or Quality Education Fund be liable to users for any incidental, consequential or indirect damages resulting from the use of the information contained in the teacher’s guide. ISBN 962-85523-0-9 Printed and bound by Potential Technology and Internet Ltd. Contents Preface iv Teachers’ Concerns about Inquiry-based Laboratory Work 1 Secondary 4 – 5 Guided Inquiries 1. How much sodium bicarbonate is in one effervescent tablet? 4 2. What is the rate of a lightstick reaction? 18 3. Does toothpaste protect teeth? 29 4. -
Bio 215 Course Title: General Biochemistry Laboratory I
NATIONAL OPEN UNIVERSITY OF NIGERIA SCHOOL OF SCIENCE AND TECHNOLOGY COURSE CODE: BIO 215 COURSE TITLE: GENERAL BIOCHEMISTRY LABORATORY I 1 BIO 215: GENERAL BIOCHEMISTRY LABORATORY I Course Developer: DR (MRS.) AKIN-OSANAIYE BUKOLA CATHERINE UNIVERISTY OF ABUJA Course Editor: Dr Ahmadu Anthony Programme Leader: Professor A. Adebanjo Course Coordinator: Adams Abiodun E. 2 UNIT 1 INTRODUCTION TO LABORATORY AND LABORATORY EQUIPMENT CONTENTS 1.0 Introduction 2.0 Objectives 3.0 Main Body 3.1 What is a Laboratory? 3.2 Laboratory Equipment 4.0 Conclusion 5.0 Summary 6.0 Tutor-marked Assignments 7.0 References/Further Readings 1.0 INTRODUCTION Scientific research and investigations will be of little value without good field and laboratory work. These investigations are normally carried out through the active use of processes which involves laboratory or other hands-on activities. Many devices and products used in everyday life resulted from laboratory works. They include car engines, plastics, radios, televisions, synthetic fabrics, etc. 3 2.0 OBJECTIVES Upon completion of studying this unit, you should be able to: 1. Define the meaning of laboratory 2. List different types of laboratories 3. Identify different types of laboratory equipment 3.0 MAIN BODY 3.1 What is a Laboratory? A laboratory informally, lab is a facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed. It is a place equipped for investigative procedures and for the preparation of reagents, therapeutic chemical materials, and so on. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories. -
Conformational Twisting of a Formate-Bridged Diiridium Complex Enables Catalytic Formic Acid Dehydrogenation
Dalton Transactions Conformational Twisting of a Formate-Bridged Diiridium Complex Enables Catalytic Formic Acid Dehydrogenation Journal: Dalton Transactions Manuscript ID DT-ART-08-2018-003268.R1 Article Type: Paper Date Submitted by the Author: 01-Sep-2018 Complete List of Authors: Lauridsen, Paul; University of Southern California, Loker Hydrocarbon Research Institute Lu, Zhiyao; University of Southern California, Chemistry; Celaje, Jeff; University of Southern California, Loker Hydrocarbon Research Institute Kedzie, Elyse; University of Southern California, Loker Hydrocarbon Research Institute Williams, Travis; University of Southern California, Loker Hydrocarbon Research Institute Page 1 of 8 PleaseDalton do not Transactions adjust margins Journal Name ARTICLE Conformational Twisting of a Formate-Bridged Diiridium Complex Enables Catalytic Formic Acid Dehydrogenation Received 00th January 20xx, Paul J. Lauridsen, Zhiyao Lu, Jeff J. A. Celaje, Elyse A. Kedzie, Travis J. Williams* Accepted 00th January 20xx We previously reported that iridium complex 1a enables the first homogeneous catalytic dehydrogenation of neat formic acid and DOI: 10.1039/x0xx00000x enjoys unusual stability through millions of turnovers. Binuclear iridium hydride species 5a, which features a provocative C2-symmetric www.rsc.org/ geometry, was isolated from the reaction as a catalyst resting state. By synthesizing and carefully examining the catalytic initiation of a series of analogues to 1a, we establish here a strong correlation between the formation of C2-twisted iridium dimers analogous to 5a and the reactivity of formic acid dehydrogenation: an efficient C2 twist appears unique to 1a and essential to catalytic reactivity. Synthetic studies of the initiation sequence for our catalyst Introduction enabled us to identify several species present in the conversion of 21 Formic acid (FA) is a promising hydrogen carrier, because it is a 1a to our active catalyst (Scheme 2). -
ON the Coivjposition of WATER.'
NATURE [March 14, 1889 overlooked in the general theory of inheritance. I am fully be no lighter than that formerly obtained from sulphuric aware that I shall be accused of flat Lamarckism ; but a nickname acid. is not an argument. MARCUS M. HARTOG. I have also tried to purify hydrogen yet further by Cork, March 6. absorption in palladium. In his recent important memoir (Amer. Clzem.Journ., vol. x. No. 4), "On the Combustion of A Fine Meteor. Weighed Quantities of Hydrogen and the Atomic Weight of A FINE meteor was visible here to-night at 6.36 p.m. It fell Oxygen," Mr. Keiser describes experiments from which it' perpendicularly almost due north-north-east, disappearing about appears that palladium will not occlude nitrogen-a very 20° ab:>ve the horizon, and was then as nearly as pos-ible of the probable impurity in even the most carefully prepared brilliancy and co lour of Venus, which was shining in the south· gas. My palladium was placed in a tube scaled, as a west at the tim e. Length of path, I think, about 20', but I am lateral attachment, to the middle of that containing the not positive that I saw the beginning of it. phosphoric anhydride; so that the hydrogen was sub B. "\Vo0DD SMITH. mitted in a thorough manner to this reagent, both before Hampstead Heath, N. W., March 11. and after absorption by the palladium. Any impurity that might be rejected by the palladium was washed out of Bishop's Ring. the tube by a current of hydrogen before the gas was collected for weighing. -
There Was Also a Metal
Respiration of Phycomyces by S.R. de Boer. INTRODUCTION. METHODS AND APPARATUS. the is of In following pages a description given experiments on the respiration of Phycomyces Blakesleeanus Burgeff. This fungus is wellknown under the name of Phycomyces but showed nitens Kunze, two years ago, Burgeff (16) that the latter name really belonged to another Phycomyces, so he called the former Phycomyces Blakesleeanus. In all the experiments transfers were used from a one culture of obtained from the spore a + strain, „Centraal- bureau voor Schimmelcultures” at Baarn, Holland. Two kinds of respiration apparatus were used, one of and the other of the closed the air current type space or Regnault type. Respiration, consisting in evolving carbon dioxide and measured. absorbing oxygen, is generally 1° the C0 off by determining 2 given 2° 0 taken in „ „ „ 2 3° both methods simultaneously. ,, using The first method has already been worked out by Pettenkofer (69); later on Pfeffer (70, 95) introduced it into plant-physiology. This socalled Pettenkofer-Pfeffer method consists in forcing or sucking a current ofair depriv- ed of carbondioxide through the respiration vessel. In leaving it the air has to pass a solution of bariumhydroxide in long horizontal glass tubes, called Pettenkofer-tubes. The of C0 off the can be deter- quantity 2 given by plant 118 mined from its absorption by the barytawater and sub- sequent titration. The air current can be led alternately into different tubes. Another absorber with barytawater behind the Pettenkofer-tubes will tell that all the C0 2 has been absorbed in the tube, if the solution in the absorber remains clear. -
13-Calc of Ideal Gas Constant
Experiment 13 - Calculation of the Ideal Gas Constant According to both theory and experiment, the pressure (P) of any sample of an ideal gas is inversely proportional to its volume (V) and directly proportional to its absolute temperature (T) and to the number of moles (n) of the gas present in the sample. This proportionality may be written: in which a is read "is proportional to." It is more convenient to put this relationship in the form of an equation: in which R, the “proportionality constant” is usually called the “ideal gas constant.” This equation is more familiar in the rearranged form PV = nRT, and this equation is called the “ideal gas equation” or the “ideal gas law.” The object of the present experiment is to verify this equation for a sample of hydrogen gas, H2 (g). To do this, we must measure P, V, T, and n. The value of R can then be calculated and compared with the accepted value of R. In this experiment, P, V, and T will be measured directly, while n will be calculated from the amount of magnesium used to produce the hydrogen gas according to the equation: Mg (s) + 2 HCl (aq) ® MgCl2 (aq) + H2 (g) Safety Precautions: • Wear your safety goggles. • Use caution when handling 6 M HCl. It is corrosive and can burn your skin. If any HCl comes into contact with your skin, rinse it off immediately and thoroughly with lots of water. Waste Disposal: • At the end of the experiment, the HCl solution will be much more dilute. -
6—Evaluation of the Gas Law Constant
6—Evaluation of the Gas Law Constant Name: ______________________________________________ Date: ________________________________________________ Section: _____________________________________________ Objectives • Measure the value of the gas constant R • Use Dalton’s Law to calculate the partial pressure of hydrogen in a closed container • Learn to collect a gas by displacing water from a closed container • Additional experience with the uncertainty of physical measurements • Additional experience with significant figures • Additional experience with average, deviation, average deviation and relative average deviation Pre-Laboratory Requirements • Read chapter 5.1-5.4 in Silberberg • Watch the instructional video titled “Eudiometer” • Pre-lab questions (if required by your instructor) • Laboratory notebook—prepared before lab (if required by your instructor) Safety Notes • Eye protection must be worn at all times. • Hydrochloric acid is caustic and should not come in contact with your skin or clothing. Wear gloves when handling hydrochloric acid. A lab coat or lab apron is recommended. • Hydrogen is highly flammable; there should be no open flames or electrical sparks in the area Discussion Gases, liquids, and solids constitute the three common forms of matter. This experiment gives you the opportunity to explore several properties of gases and to measure a value for the international gas constant R. Gases expand to occupy the container in which they are placed and any gas is less dense than the liquid or solid form of a substance. In addition to expanding to completely fill containers, gases exert pressure on the walls of the container and the pressure increases with increasing temperature. The relationships between volume, pressure, and temperature are summarized in Charles’ law in the Boyle’s law.