Important thermodynamic information, such as the enthalpy of combustion, could be obtained by measuring the temperature change. The bomb is immersed in a quantity of water and surrounded by an adiabatic shield that serves as the heat insulator. In this experiment, a commercial bomb calorimeter (Parr) is used to determine the heat of combustion of an organic compound. The sample is held in a cup that is placed near the ignition wire that is used to start the combustion reaction as shown in Figure 1. Figure 1: Schematic of a constant volume bomb calorimeter.
Objective To determine of heats from three exothermic reactions and investigate the Hess Law Summary Based on this experiment, we have study three related exothermic reactions involving sodium hydroxide. The first reaction (Part A), solid sodium hydroxide will dissociate into water. The heat produce by this reaction (∆H1) and this called as the heat of solution of solid NaOH. From the experiment we have managed to determined that ∆H1 = -41.84 KJ/mol In the second reaction (Part B), an aqueous solution of NaOH is allowed to react with an aqueous solution of HCl. This is a neutralization reaction between a strong acid and strong base.
The lesson of the lab is to teach us about Chemical kinetics, speeds and arrangements of molecules in a reaction during the process it goes from reactants to products. The reaction rates can be determined by two different kinds of equation. The average rate and the instantaneous rate. One is calculated by a change in time, and the other is calculated by a rate at a particular time a reaction has begun. Equations and mechanisms: Rate=k[A]^x [B]^y Rate=k[I]^x [S2O8]^y Rate1 k[A]1^x [B]1^y Rate2 k[A]2^x [B]2^y Rate3 k[A]3 [B]3 K=Ae -Ea/RT activation energy 2I-(aq)+S208^2-(aq)------> I2(aq)+2SO4^2-(aq) I2(aq)+ 2S2O3^2-(aq)------>2I-(aq)+S4O6^2-(aq) Apparatus and supplies: stopwatch, constant water bath, stirring rod, 10x75mm test tubes (5), 1ml pipet, 2ml pipet Chemicals: 0.200 M KI, 0.100 M K2S2O8, 0.0005 Na2S2O3, 2% starch solution.
Chemistry 11 | The Decomposition Reaction of Baking Soda, NaHCO3 | Oscar ShiPeriod 2Laboratory AssignmentDue Date: 2011/4/14 | Introduction The objective of this experiment is to find the actual chemical equation that governs the manner in which baking soda (sodium hydrogen carbonate NaHCO3) decomposes. When NaHCO3 is heated, it decomposes to produce a gas and leaves behind a solid. Two possible equations for the decomposition are: NaHCO3 (s) + heat NaOH (s) + CO2 (g) NaHCO3 (s) + heat ½ Na2OH3 (s) + ½ H2O (g) + ½ CO2 (g) Materials and Methods * electronic balance * sodium hydrogen carbonate * ring * ring stand * crucible tongs * crucible * crucible lid * clay triangles The Procedure of the Laboratory 1. Put on safety goggles and a lab apron. 2.
Purpose: To identify a certain element by flame testing it in a bunsen burner and determining the wavelength of the light released. The wavelength and the colors shown using the spectroscope determine the element that has been tested. Also, to correctly use the bunsen burner, and the spectroscope. Introduction: When electrons absorb energy and become excited, they eventually fall back into ground state which allows them to release light energy. Each different element releases a different wavelength of light which results in different colors of light.
Ghostbuster Slime Lab 10/4/2012 Abstract The purpose of this experiment was to observe the physical properties and changes of the creation of a polymer as a result from cross-linking. A borax solution was made and was combined with a polyvinyl alcohol solution. A polymer’s cross-links give them many properties, like bonding ability, elasticity, and viscosity. The amount of water added in the experiment directly affected the viscosity and elasticity of the slime polymer. Too much water added resulted in a high viscosity and low elasticity.
They go in order of the rainbow; red being the weakest and violet being the strongest. PURPOSE: The purpose of this experiment is to burn atoms of a metal using a flame burner to see how much energy a photon releases by the color of light emitted. Also by observing the photon; the ability to specify an unknown substance will be available. PROCUDURE: Seven well plates were obtained and labeled with the name of the known substances. In each well plate place a small amount of known substances into the well plate.
PURPOSE/INTRODUCTION The purpose of this experiment is to produce visible emissions from heating different metal fluorides with a Bunsen burner. The hypothesis is that by warming the different metal chlorides, the different elements found in each chloride will produce a different color when placed in the flame. We will also produce a table of our findings with our information we recorded from the results gathered in this lab. In the preceding discussion, we will be testing different metal chloride reactions when a flame is introduced to them. MATERIALS * One Bunsen burner * 1 gram of Sodium Chloride * 1 gram of Potassium Chloride * 1 gram of Lithium Chloride * 1 gram of Barium Chloride * Nichrome wire (wire with a loop) * 0.4 grams of water * Protective eyewear * Lab gloves Barium is a toxic metal, be sure to wear gloves and goggles when handling this material, also if using a Bunsen burner be sure to turn of the gas.
Lastly, the final product was analyzed by mass spectrometry and HNMR. Reaction setups: Drawing of the new apparatus is attached. Spectra: Please see attached GC-MS and HNMR. Calculations: Mechanism: Conclusion: The hydroboration-oxidation reaction is a reaction that is used to form an alcohol from an alkene. In this reaction there were two isomers of an alcohol formed.
An Investigation to determine the reaction kinetics of the Iodine-Propanone reaction The Aim for this investigation to use the reaction between Iodine and Propanone, with an acid catalyst, to determine the reaction kinetics of each of the reactants and find out which order each of the reactants is and to develop a rate equation. This will be done by changing the concentrations of the reactants and reacting them in a colorimeter and measuring the colour change over time by measuring the percentage of light absorbed over a constant period of time. Equation- CH3COCH3(aq) + I2(aq) → CH3COCH2I(aq) + H+(aq) + I-(aq) Source- http://www.chemtopics.com/unit09/iodina.pdf This is a substitution reaction because a Hydrogen atom gets substituted for an Iodine atom. The role of the acid catalyst is to speed up the otherwise slow rate of reaction. Nuc: + R-LG → R-Nuc + LG: The electron pair (:) from the nucleophile (Nuc) attacks the substrate (R-LG) forming a new bond, while the leaving group (LG) departs with an electron pair.