Experiment - determination of the valency of magnesium
Title: Determination of the Valency of Magenesium Objective: . To study the quantitative relations between amounts of reactants and products of a reaction. 2. To determine the reaction of stoichiometry of know starting mass of magnesium and the measured collection of hydrogen gas. Apparatus and Material: Electrical balance, rubber band, watchglass, glass rod, burette, beaker, thermometer, pipette, gauze, barometer, retort stand, funnel Procedure: . The burette was used upside down to collect the hydrogen. The volume of the unmarked space in a clean, dry 50cm3 burette was determined by pipetting 25.00cm3 of water into the vertically clamped burette (right way up).The burette reading was noted, drained and repeated. The water in the burette was left for 10 min. and checked for leaks. 2. A piece of magnesium was cleaned with steel wool. A piece was cut with scissors within the length shown. The ribbon was curled up. A watch glass was tare on the four decimal balance and the magnesium ribbon was ACCURATELY weighed between0.0300 and 0.0360g on the watch glass, which then was placed inside a 600cm3 beaker. 3. A small filter funnel with a short stem (1.0-1.5cm long) was taken and covered with gauze. The watch glass was invert and placed over the magnesium. 4. The beaker was carefully filled with (tap) water until the level was approximately 0.5-1.0cm above the end of the
Hydrolysis of Salts and choice of Indicators / Titration Curve
UNIVERSITI TUNKU ABDUL RAHMAN FACULTY OF SCIENCE KAMPAR CAMPUS BACHELOR OF SCIENCE (HONS) BOTECHNIOLOGY YEAR 1 SEMESTER 1 CHEMISTRY LABORATORY 1B UESB 1212 Lecturer : Ms. Eng Mei Hsuan Student's Name : Panmalar D/O Krishnamoorty Student's ID : 09ADB07367 Experiment Number : 3 Title : Hydrolysis of Salts and choice of Indicators / Titration Curve Date : 25/02/2011 TITLE : Hydrolysis of salts and choice of indicators / titration curves OBJECTIVE : . To study the pH of different salts solutions. 2. To calculate the degree of hydrolysis N and acetate ions. 3. To determine a good indicator for a selected acid-base titration. INTRODUCTION: Many salts dissolve in water to give neutral solutions. Some salts however, react with water to form acidic or alkaline solutions. These reactions are described as salt hydrolysis. A salt is an ionic compound containing positive ions other than H+ and negative ions other than OH-. The ions contained in salts can act as acids or bases in an aqueous solution. Cations act as acids that react with water to produce hydronium ions and anions as bases that react with water to produce hydroxide ions. Salts can be thought as being derived from the neutralization of an acid or a base. A salt formed from a strong acid and a strong base will not react with water. Bronsted-Lowry proton transfer theory. According to this concept, any
Separation of Liquids by Simple Distillation and Analysis by Gas Chromatography
Separation of Liquids by Simple Distillation and Analysis by Gas Chromatography Nighat Ali June 26, 2011 Methods and Background The purpose of this lab is to separate a 1:1 mixture of ethyl acetate and butyl acetate by simple distillation, which is then analyzed by gas chromatography. The chromatography test will then assure us if the distillation gave us a good separation of ethyl acetate and butyl acetate (Figure 1). Both compounds have almost similar structures due to the presence of an ester group. This is the only similarity shared between these compounds, however they differ in their boiling point, dipoles, attractive forces, number of atoms, number of electrons and equilibrium vapor pressure. These differences then help in determining the relation between compound and two immiscible phases. The separation of mixture is obtained based on different boiling points of both compounds where ethyl acetate has a boiling point of 77° C and butyl acetate has a boiling point of 126° C. As the mixture is heated, the first compound to vapor will be ethyl acetate due to its lower boiling point and as the temperature increases, there will be less ethyl acetate in the mixture. At around 77° C - 80° C, the vapor that being condensed should contain both compounds and an increase in the temperature will be observed. Then, after the temperature becomes steady around 122° C -
Steam Distillation of (S)-(+)-Carvone from Caraway Seeds and (R)-(- )-Carvone from Spearmint Leaves. Analysis of Products by Infrared Spectroscope and TLC
Steam Distillation of (S)-(+)-Carvone from Caraway Seeds and (R)-(-)-Carvone from Spearmint Leaves. Analysis of Products by Infrared Spectroscope and TLC Nighat F. Ali July 6, 2011 Methods and Backgrounds The objective of this lab experiment was to isolate (S)-(+)-Carvone from Caraway Seeds and (R)-(-)-Carvone from spearmint leaves through process of steam distillation by extracting the distillate with CH2Cl2. In addition, infrared spectroscopy, Bayer test, and thin-layer chromatography was performed to analyze the distillate samples. By performing such methods, the enantiomers of the carvone were examined. In the liquid phase, the molecules are constantly in motion. Some molecules at the top of the surface escape to the vapor phase. A closed system is in dynamic equilibrium when the number of gas molecules exiting the liquid phase is equal to the number of gas molecules entering the liquid phase. The vapor pressure of a liquid is the pressure that the gas molecules exert against the walls when they collide. Vapor pressure increases as temperature increases because the molecules have more kinetic energy. More molecules escape to the gas phase. The boiling point is where the vapor pressure equals the total atmospheric pressure. Therefore, the higher the vapor pressure, the more molecules are in the gas phase. The boiling point would be lower since more gas molecules
The aims of this experiment are to measure the heat of decomposition of hydrogen peroxide the heat capacity of calorimeter and calculate the enthalpy of decomposition of hydrogen.
SINGAPORE POLYTECHNIC SCHOOL OF CHEMICAL LIFE SCIENCES Diploma of Applied Chemistry with Pharmaceutical Science Experiment 3 Heat of Decomposition of Hydrogen Peroxide Date of Experiment: 25/11/10 CP4117 Desmond Seah (P1006812) Year of Study: Year 1 DACP/FT AY 10/11 ________________ Content Page Synopsis Page . Introduction 1-2 2. Theory 2-6 3. Procedure 7 4. Results and calculation 8-10 5. Discussion 10-11 6. Conclusion 12 7. Recommendation References List of Illustration S/N Figures and Tables Page Number Simple calorimeter 4 2 Bomb calorimeter 5 3 Suggested setup for simple calorimeter 11 Synopsis The central objectives of this experiment are
Synthesis of different cobalt compounds through ligand exchange was performed in this laboratory. Electroconductivities and Infrared spectrophotometry of the compounds were conducted to observe the effects of the exchanges.
Abstract Ligand exchange is among the most popular topics in the area of metal complexes. One of the interesting aspects of cobalt ligand exchange is its slow reactivity. Because of this, it is possible to study cobalt complexing with much greater intensity than other metals allow. Synthesis of different cobalt compounds through ligand exchange was performed in this laboratory. Electroconductivities and Infrared spectrophotometry of the compounds were conducted to observe the effects of the exchanges. With this in mind, we delved deeper into ligand exchange by attempting to synthesize another cobalt compound using the bidentate ligand, 2,2 bipyridine. Introduction Cobalt has a coordination number of six, which means that there are six points of ligand attachment, leading to cobalt's ability to form octahedral complexes: Figure 1: Cobalt's octahedral structure Cobalt forms such complexes by reacting with Schiff bases and macrocyclic ligand complexes. (Hop, 1996) Schiff bases, or imines, are compounds that contain a carbon double bonded to an oxygen, resulting from the nucleophilic addition reaction between an aldehyde and a primary amine. (Bailey, 1995) This ability of cobalt to form so many different complexes is of great interest because it allows chemists to explore many important chemical concepts. (Gahan, 1989) Synthesis of cobalt III complexes can be
Separation and Identification of Organic Unknowns.
University of Paisley Department of Chemistry and Chemical Engineering Organic Chemistry Laboratory Report Separation and Identification of Organic Unknowns October 2001 Christopher Lundie Industrial Chemistry Contents Page Aim 2 Introduction 2 Experimental Method 4 Results and Discussion 8 Conclusion 13 Appendix 1 - Questions 14 Appendix 2 - IR Spectra 16 Aim The purpose of this laboratory experiment was two-fold, first, to demonstrate the extraction of acidic, basic and neutral components from a crude product, finally determining what unknowns were present using some common analytical procedures and techniques. Introduction An organic crude product obtained from a 'worked up' reaction mixture will in almost all cases need to be purified further. The work-up, by which this procedure is usually known, simply refers to the isolation of the product from the reaction mixture, free from solvent and spent reagents, and does not imply any purification. In order to purify an organic compound by separating the impurities, one has to rely on the desired compound having different properties to the impurities. Differences that may be taken advantage of are: differences in solubility, volatility, polarity, shape and functional groups present. For example, crystallisation relies on the differences in solubility between the desired compound and the
Determination od the level of acetic acide in lime juice
Name: Simon Henry Opio-Emuna Module: TEP041N Date: 11th. November 2008. Title: The experiment to determine the percentage of citric acid in the lime juice sample by using the standardised volume of sodium hydroxide solution. Introduction The experiment involved the measurement of the % of citric acid in lime juice sample by titrating with the standardised solution of sodium hydroxide. Sodium hydroxide is deliquescent solid (absorbs moisture from the atmosphere) and because of this it is not possible to prepare a standard solution of sodium hydroxide from weighing. In solution sodium hydroxide reacts with carbon dioxide from the atmosphere to form sodium carbonate therefore lowering its concentration. The solution of potassium hydrogen phthalate (KHP, KHC8H4O4, RMM = 204.23g/mol) was used as primary standard. Potassium hydrogen phthalate is a monobasic acid reacts with sodium hydroxide in a ration of 1:1. It is a suitable primary standard because: It has a high relative molecular mass, soluble in water and stable in the atmosphere (non-hygroscopic and uncreative). In water KHP dissociates releasing hydrogen phthalate ion (HC8H4O4-) weak acid. KHP reaction in Water KHC8H4O4(aq) K+(aq) + HC8H4O4-(aq) Weak acid. In solution one mole of KHP (primary standard) contains one mole of H+ that can react with one mole of sodium hydroxide which contains one mole of OH- ions.
Rheology. This report is demonstrating the relationship between the viscosity of a solution and temperature, concentration and shear rate. This report is going to analyse the reasons why there is a decrease positive relationship between viscosity and conc
PY1070, Rheology abstract Characterisation of rheological behaviour of pharmaceutical fluids This report is demonstrating the relationship between the viscosity of a solution and temperature, concentration and shear rate. This report is going to analyse the reasons why there is a decrease positive relationship between viscosity and concentration and a negative relationship between viscosity and temperature and also shear rate. 3 experiments are conducted to prove the hypothesis above. The results of the experiments are explained in terms of intermolecular forces between the molecules in solutions. Viscosity is the resistance for a fluid to flow. Shear stress and shear rate are defined as the force and speed of moving a fluid respectively. Rheology is the study of these viscous fluids and their movement and deformation properties. Part 1 In the part 1 of the experiment, the viscosity of 3 different concentrations of methylcellulose is measured using a Brookfield viscometer (50 r.m.p). As shown on the graph, the viscosity has a direct relationship with the concentration. As shown below, the structure of methylcellulose encompasses a hydrophilic structure which forms hydrogen bond when mixed with water. As the concentration of methyl cellulose increases so does the number of hydrogen bonds hence the solution becomes more viscous. Graph 1 below confirms the theory
Investigating the Rate of Cooling
SC1 Investigating the Rate of Cooling By Rachel Armstrong Plan In this Sc1 I am going to investigate the way water cools down under different circumstances. I am going to change some variables and see how this affects the way the water cools down .I am going to look at four different variables. * How layers of Insulation affect the rate of cooling. * How varying the Start temperature affects the rate of cooling. * How a fan will affect the rate of cooling. * How a lid will affect the rate of cooling. I used both Focus Investigations and a real experiment for my results. The real experiment I did was - How does a lid affect the rate of cooling. I also did a control experiment along side this one, so I will be able to compare this to the other results to see how much the variables effect the final result. Method I am going to do most of the experiment on Focus Investigations. For all of the experiments I am going to keep the mass of water at 50cm³ and for all except the experiment where I will very the start temperature I am going to keep the start temperature constant at 100º. I will then use a thermometer to measure the temperature every 10 or 5 minutes depending on the experiment, I shall record the results then put them on a graph and compare them with the control experiment. The room temperature is 20ºC on the computer experiments, but in the classroom it is
