...EXPERIMENT 3 Title : EXPERIMENTAL APPLICATIONS OF HESS’S LAW Objective : To determine the heat of reaction by applying Hess’s Law for reactions whose energy cannot be easily measured directly. Introduction An exothermic reaction releases heat into the surroundings and is usually observed as temperature increases in the solvent, container, and other immediate surroundings. The amount of heat released from the reaction can be expressed as q reaction = q solution + q calorimeter ……..(1) In this experiment, the calorimeter is assumed to absorb so little heat that q calorimeter is nearly zero and thus the equation simplifies to q reaction = q solution ……...(2) The temperature change caused by the addition of a given amount of heat will depend on the specific heat, Csp of the substance. Thus, the heat involved can be calculated by the equation Q = (Csp)(m)(T) ………(3) The mass of the substance is m, and the change in temperature is T (final temperature – initial temperature) Since this experiment is run at constant pressure, thus the heat changes observed will be equal to the enthalpies of reaction, H for the reactions considered. The enthalpies of these directly observed reactions and Hess’s law will be used to calculate the enthalpy change for an additional reaction which is not directly observed. Recall that since enthalpy is a state function, the enthalpy change for any process will depend only on the initial and final states...
Words: 1570 - Pages: 7
...Title: Experimental Applications of Hess’s Law Objectives: 1) To study and understand the experimental method of Hess’s law. 2) To interpret experimental data by applying Hess’s law. 3) To determine the H of ammonium chloride solid to ammonia gas and hydrochloric acid gas by using Hess’s law. Introduction: A reaction that release heat to surrounding is known as exothermic reaction. It is usually observed as temperature increases in solvent, container and other immediate surroundings. The expression of heat released from the reaction is: qreaction = qsolution + qcalorimeter ……..(1) The qcalorimeter is nearly zero because the calorimeter in this experiment is assumed to absorb little heat. So, the equation is simplified to qreaction = qsolution ……...(2) The change in temperature that caused by the addition of a given amount of heat will depend on specific heat, Csp of substance. Therefore, the heat involved is calculated by the equation Q = (Csp)(m)(T) ………(3) Mass of substance is m, change is temperature is T (final temperature – initial temperature). The heat changes observed is equal to enthalpies of reaction, H for the reactions considered because this experiment was run at constant pressure. The enthalpy of these directly observed reactions and Hess’s law was used to calculate the enthalpy change for an additional reaction which is not directly observed. Hess’s law stated that the overall enthalpy...
Words: 2189 - Pages: 9
...FINAL EXAM CHEM 1310 FS11 VERSION GREEN Name: ____________________ 1.|How many liters of chlorine gas at 25°C and 0.950 atm can be produced by the reaction of 12.0 g of MnO2? MnO2(s) + 4HCl(aq) ® MnCl2(aq) + 2H2O(l) + Cl2(g)| A)|3.55 L| B)|3.09 L| C)|0.138 L| D)|5.36 ´ 10-3 L| E)|0.282 L| 2.|A 6.0-ft person weighs 168 lb. What is this person's height in meters and weight in kilograms? (1 lb = 453.6 g; 1 m = 3.28 ft.)| A)|5.4 m, 76.2 kg| B)|1.8 m, 76.2 kg| C)|2.3 m, 43.2 kg| D)|1.8 m, 7620 kg| 3.|The speed of sound in air at room temperature is about 343 m/s. What is this speed in miles per hour? (1 mi = 1609 m.)| A)|12.8 mph| B)|343 mph| C)|767 mph| D)|46020 mph| 4.|The oxidation number of Fe in K3Fe(CN)6 is| A)|-3| B)|+3| C)|+2| D)|-4| E)|+1| 5.|What is 25.4 mg when converted to kilograms?| A)|2.54 kg| B)|2.54 ´ 104 kg| C)|2.54 ´10–5 kg| D)|2540 kg| 6.|What is the formula for copper (II) cyanide?| A)|Cu(CN)2| B)|Cu2CN| C)|CuNCO| D)|CuCN| 7.|What is the molar mass of acetaminophen, C8H9NO2?| A)|125 g/mol| B)|162 g/mol| C)|76 g/mol| D)|43 g/mol| E)|151 g/mol| 8.|Calculate the mass of iron(II) sulfide formed when 27.66 g of Fe reacts with 14.44 g of S.| A)|9.17 g| B)|5.27 g| C)|39.60 g| D)|14.44 g| E)|43.54 g| 9.|Aluminum is a lightweight metal (density = 2.70 g/cm3) used in aircraft construction, high-voltage transmission lines, beverage cans, and foils. What is its density in kg/m3?| A)|8.2 ´ 102 kg/m3| ...
Words: 1514 - Pages: 7
...In: Business and Management Mis Exam Chapter 01:An Introduction to Information Systems TRUE/FALSE 1. Information and data are essentially the same thing. ANS: F PTS: 1 REF: 5 2. Computers are required to organize or process data. ANS: F PTS: 1 REF: 7 3. Using a computer to forecast future sales and order more inventory before a shortage can occur is an example of information system feedback. ANS: T PTS: 1 REF: 12 4. A CBIS is a single set of hardware, software, databases, telecommunications, people, and procedures configured to collect, manipulate, store, and process data into information. ANS: T PTS: 1 REF: 12 5. The technology infrastructure is a set of shared IS resources that form the foundation of each computer-based information system. ANS: T PTS: 1 REF: 12 6. Today’s more advanced processor chips have the power of 1990s-era supercomputers. ANS: T PTS: 1 REF: 13 7. Teraflops is a measure of computer storage capacity. ANS: F PTS: 1 REF: 13 8. Application software such as Windows Vista and Windows Seven control basic computer operations such as start-up and printing. ANS: F PTS: 1 REF: 14 9. Software is needed for computers of all sizes from cell phones and small hand held devices to the largest supercomputers. ANS: T PTS: 1 REF: 14 10. Private cloud computing applications are available to everyone. ANS: F PTS: 1 REF: 15 11. Information about the documents on the Web and access to these documents are controlled...
Words: 497 - Pages: 2
...THERMOCHEMISTRY OF NaOH AND HCl LAB Overview Teacher’s Instruction: Find the Molar Heat of Reaction for the NaOH reaction. Then, predict and calculate the change in enthalpy (ΔE) and change in heat (ΔH) when 5.00g NaOH reacts completely with HCl. Reaction Equation: NaOH(s) + HCl(aq) -> NaCl(aq) + H2O(liq) Net Ionic Equation: Na(OH)(s) + H+(aq) -> H2O(liq) + Na+(aq) The Big Question: If we combine solid NaOH and aqueous HCl, how will the temperature change? What will the change be with, specifically, 5.00g of NaOH? Scientific Background and Principle: WELL, I’ll have you know that we got our hands on a fancy-schmancy Lab Quest 2 with a temperature probe. Now this device allows us to accurately record the temperature of a given entity over a period of time; as such, by having the Lab Quest record the temperature of the system, we were able to gather the total temperature change for the reaction. In theory, the temperature should increase by 53.10o Variables * Independent Variable: Amount of NaOH * We had a theoretical value for temperature that was dependent on the amount of NaOH used; as such, we set our amount at a certain point to achieve that temperature. * Dependent Variable: Heat of Reaction (Temperature) * We measured the temperature of the reaction throughout its duration, which would have varied in intensity and duration based on the amount of NaOH we used * Controlled Variables * Light-- by enclosing the reaction in darkness...
Words: 1848 - Pages: 8
...Earth Science: Volcanoes Report by: Kenneth Ragragio What is Volcanoes? * Volcanoes are vents that allow lava, rock fragments and gases to escape from layers beneath the earth's surface. Learn how volcanoes form both on land and underwater and why they erupt. * Volcanoes are spectacular events and because of this, they have found their way into the plot of many Hollywood movies. While the movies have given most of us the vivid image of red-hot lava spewing out of the top of a towering volcano, they do not share the entire story of volcanoes Magma and Lava * So what exactly is a volcano? Well, it can be defined as a vent in the earth's crust through which lava, rock fragments, hot vapor and gases are ejected. In other words, a volcano is the earth's way of letting off a little steam. * The super-heated particles that eject out of a volcano come from deep below the earth's surface where temperatures can become so hot that rock actually melts. Magma is the term used to describe this hot molten rock from deep within the earth. * A volcano begins to form when magma, which is less dense than the rock it originated from, rises toward the earth's surface. This liquid rock collects in chambers called 'magma chambers,' where pressure builds due to expanding steam and gases associated with the magma. As pressure reaches a peak within these chambers, magma finds its way through a vent or fissure in the earth's surface, resulting in a volcanic eruption and the expulsion...
Words: 5922 - Pages: 24
...ELECTROCARDIO-graphy (E.C.g.) Uses: - To detect arrhythmias To diagnose chamber hypertrophy To diagnose myocardial infarction Electrocardiogram is the graphic representation of electrical changes occurring in the cardiac muscle. It is recorded by using surface electrodes. These are of two types: Bipolar leads Unipolar leads Bipolar leads Lead I-Right wrist and left wrist Lead II –Right wrist and left ankle Lead III- Left wrist and left ankle Unipolar leads - Limb leads and chest leads a. Limb leads- aVR – right wrist aVL –left wrist aVF – left ankle b. Chest leads- V1-4th right intercostal space at the sternal border V2-4th left intercostal space at the sternal border V3- between V2 & V4 V4- at the midclavicular line in the left 5th intercostal space V5- at the anterior axillary line in the same horizontal plane V6- at the mid-axillary line in the same horizontal plane V3R - on the right side – position same as that of V3 V4R - on the right side – position same as that of V4 E.C.g. - - paper speed-25mm/sec horizontally 1mm(one small square)=0.04sec (one large square=0.04x5=0.2sec vertically 1mm=0.1mv P-wave- atrial depolarisation –upright width – 2.5mm=0.1sec QRS - ventricular de-polarisation width – 1-2.5mm=0.04-0.1sec average 0.08sec height – variable PR- interval-from...
Words: 838 - Pages: 4
...Industrial Area Development Act. It is also home to the Noida Film City. Noida is located in Gautam Budh Nagar district of Uttar Pradesh state. The district's administrative headquarters are in the nearby town of Surajpur. However, the district's highest government official, the District Magistrate (DM), resides in Noida. The city is a part of the Noida-Dadri Vidhan Sabha (state assembly) constituency and Gautam Budh Nagar Lok Sabha (parliamentary) constituency. Noida stands at 17th place when it comes to cleanliness in India leaving far behind Gurgaon and Faridabad in the National Capital Region who stand at 87th and 237 respectively. Geography Noida is located in Gautam Budh Nagar district of Uttar Pradesh state. Noida is about 20-kilometre (12 mi) southeast of New Delhi. It is bound on the west and south-west by the Yamuna River, on the north and north-west by the city of Delhi, on the north-east by the cities of Delhi and Ghaziabad and on the north-east, east and south-east by the Hindon River. Noida falls under the catchment area of the Yamuna river, and is located on the old river bed. The soil is mainly rich and loamy[2] and is suitable for growing seasonal vegetables, grains like wheat and cash crops like sugarcane. With the advent of urbanization, vegetables and fruits are now the main crops.[citation needed]. The area's vegetation includes dry deciduous trees like Sal, Sheesham and Teak. Noida extensionNoida extension is Sector 189 and Sector 445 of Greater...
Words: 1607 - Pages: 7
...Identification and Synthesis of an Unknown Ionic Compound 3/24/16 Department of College of Natural Science, Michigan State University, Farm Lane, East Lansing, MI 48825 Chemistry 161, Section 10 Dr. Joseph Ward Abstract The goal of this experiment is to identify an unknown compound. To identify this compound a series of test were performed to find the chemical and physical properties of the unknown compound. The test performed; flame test, solubility test, halide test, acetate test, ammonium test, nitrate test, sulfur test, carbonate test, calcium test and pH test. When the flame test of the unknown resulted in a brick red color, it was determined that the unknown contained calcium. Another calcium test was tested and proved that the unknown was calcium. Since the unknown is dissolvable in water, CaCO3 was no longer a possible candidate because it is insoluble. The pH test for the unknown was 5 whereas the pH for calcium chloride is 8 and the unknown tested negative for halide, therefor calcium chloride was not an option for the unknown as well. The last calcium compound left was calcium nitrate which also had a pH of 5 and a brick red flame test color. Introduction There was an unidentified white compound found in the lab. The goal of the experiment was to identify what the unknown compound is and how to dispose of it safely. In order to find this information, the compounds chemical and physical properties needed to be determined. This was a given...
Words: 1530 - Pages: 7
...------------------------------------------------- Course Code: ACC501 Course Title: ACCOUNTING FOR MANAGERS ------------------------------------------------- Course Instructor: Sukhpreet Kaur ------------------------------------------------- Academic Task No.: 1 Academic Task Title: Company Based Assignment ------------------------------------------------- Date of Allotment: 08/30/2014 Date of submission: 9/12/2014 ------------------------------------------------- Student’s Roll no: RQ1405B58 Student’s Reg. no: 11401812 ------------------------------------------------- Evaluation Parameters: Solely based on the basic introduction and overview of the business of Hexaware Technology ltd. Learning Outcomes: From this task we came to know about the overview of company, History of the Company, Business of the Company, Management of the Company, Competitors, Future plans of the Company, SWOT of the Company. Declaration: I declare that this Assignment is my individual work. I have not copied it from any other student’s work or from any other source except where due acknowledgement is made explicitly in the text, nor has any part been written for me by any other person. Student’s Signature: Evaluator’s comments (For Instructor’s use only) General Observations | Suggestions for Improvement | Best part of assignment | | | | Evaluator’s Signature and Date: Marks Obtained: _______________...
Words: 2206 - Pages: 9
...Powell Fabrication & Manufacturing Inc The Bleach Strength Test — A Chemical Test Method to Determine the Strength of Sodium Hypochlorite Last Update: March 30, 2001 Background The liquid sodium hypochlorite made by the Powell Continuous Bleach Manufacturing Plant or by other methods is produced as sodium hypochlorite (NaOCl) in the presence of excess caustic. Because consumers require differing solution concentrations, bleach manufacturers need to measure specific components of the product. Sodium hypochlorite (NaOCl), excess caustic (NaOH), and excess alkalinity (Na2CO3) are components in bleach that are routinely tested. Although this test procedure does not address heavy metals and sodium chlorate (NaClO3), a decomposition product, they should be tested at intermittent intervals and will require a qualified laboratory to perform these tests. Comparative Sample Analysis The test method below will provide accurate and repeatable results by the producer and consumer to ensure the product is meeting the desired specification. However, there are times when the strength of the sodium hypochlorite as tested by the manufacturer will differ from the consumer’s results. Many times these differences can be accounted for by the losses in shipping due to decomposition. However, it is difficult to know when the differences in test results are decomposition losses and when they are errors in test methods or procedures. In order for both the manufacturer...
Words: 4272 - Pages: 18
...the only organelles, within a cell, that have their own DNA. They also use this DNA to produce their own enzymes and proteins. Further proof is shown by the fact that both these organelles have a double layer of membrane surrounding them, and that they replicate as a bacteria does. Purpose: * Prepare a supernatant of spinach leaf * Demonstrate proper techniques involved in using centrifuge * Using filtration and centrifugation, separate the chloroplast from other organelles in a spinach leaf * Identify mitochondrion in an onion cell Materials: * Fresh spinach leaves * Grinding solution * 0.33 M sorbitol * 10mM sodium pyrophosphate (NaPO) * 4mMMgCl * 2mM Ascorbic Acid * Adjust pH to 6.5 with HCl * Chopping board and knife * Chilled mortar and pestle * Cheesecloth * Refrigerated preparative centrifuge * Suspension solution * 0.33 M Sorbitol * 2mMEDTA * 1rnMMgCl * 50rnMHEPES * Adjust pH to 7.6 with NaOH * Hematocytometer and microscope * Ice bath * Sprig of elodea Procedures: Part 1: Choroplasts from Spinach Leaves 1. Prepare an ice bath and pre-cool all glassware to be used. 2. Select several fresh spinach leaves and remove the large veins by tearing them loose from the leaves. Weigh out 4.0 grams of...
Words: 1049 - Pages: 5
...CALCULATION EXERCICES To the LABORATORY EXPERIMENTS IN MEDICAL CHEMISTRY Edited by: Zoltán Matus Compiled by: Péter Jakus László Márk Anikó Takátsy Pécs, 2007 Table of content: Introduction 3 1. Stoichiometry I. Balancing equations 4 2. Stoichiometry II. Calculation exercises 9 3. The gaseous state 13 4. Concentrations of solutions 17 5. Calculations connected to titrimetry 28 6. Electrolytic dissociation 33 7. Dilute solutions 38 8. Hydrogen ion concentration, pH, buffers 44 9. Heterogeneous equilibria. Crystallisation, solubility product, partition coefficient 55 10. Thermochemistry 64 11. Electrochemistry 67 2 INTRODUCTION The chapter is devoted to helping the students practice the most important topics of General Chemistry. The order of the sections follows the schedule of the lectures and seminars, and their volume indicates the importance of the topic. Each section begins with a few solved problems. They represent the minimum requirement at the exam. The worked-out solutions are not the only ones. For an easier self-checking, the numerical results of the unsolved calculation exercises are given in parentheses after each question. Sources: 1.) Laboratory experiments in medical chemistry, ed. György Oszbach, Pécs, 1998. 2.) Villányi Attila: Ötösöm lesz kémiából, (6. ed.) Mőszaki Könyvkiadó, Budapest., 1999 3.) Charles E. Mortimer...
Words: 19522 - Pages: 79
...assists in memory formation. Basing an explanation on this concept. Carbamazepine (Tegretol) Myelosuppression is the highest priority complication that can potentially affect clients managed with carbamazepine (Tegretol) therapy. The client requires close monitoring for this condition by weekly laboratory testing. Hepatic function may be altered. Older clients usually have a decline in lean body mass and total body water that causes water-soluble drugs to become distributed in fluid compartments, resulting in an increased concentration, so determining the drug's serum level for toxicity should be implemented first. Hemorrhagic cystitis (blood in the urine) is the characteristic adverse reaction of Cyclophosphamide (Cytoxan). Metoclopramide HCl (Reglan) blocks dopamine receptors in the brain, which can cause the extrapyramidal symptoms associated with Parkinson's disease. Bone marrow depression with granulocytopenia is a severe but common adverse effect of Zidovudine (Retrovir). Careful monitoring of CBCs is indicated. Sodium bicarbonate is an effective treatment for an overdose of tricyclic antidepressants such as Amitriptyline (Elavil) to reverse QRS prolongation. Phenobarbital causes respiratory depression, so the priority intervention is assessment of vital signs. Hypokalemia (Low potassium) levels enhance the effects of neuromuscular blocking agents, so the...
Words: 1132 - Pages: 5
...prestavlja nuklearno punjenje i koji nije jos postao Ne. Međutim, gubeći jedan negativno napunjen electron on prisvaja jedno pozitivno naelektrisanje koje definišemo kao Na+. Ove vrste vise nisu neutralni atomi, ali su postali pozivno naelektrisani joni koji su nazvani katjoni, I imaju drugačije karakteristike od neutralnih atoma. Sada ćemo razmotriti Fluor u grupi VII, koji ima elektronsku kofiguraciju od 1 s2 2s2 2p5. Ako Flor može da dobije jedan electron u njegovom poslednjem omotaču, omotač će postati potpuno popunjen I dobiće inertnu kofiguraciju od Ne. 9F+ + 1e- 9F- 1s2 2s2 2p5 1s2 2s2 2p6 (2.8=Ne) U ovom slučaju, atom je dobio jedan negativno naelektrisan electron I postao je negativno naelektrisan jon koji ima naziv anjon. Ako mi uzmemo Natrijum koji lako može da izgubi elektron u prisustvu flora, koji će spremnije prihvatiti novi I zameniti mesta. Činjenica da će zamena biti vise entuzijastička nego...
Words: 1964 - Pages: 8
