Kinetics: The rates of a chemical reaction
UNIVERSITI TUNKU ABDUL RAHMAN FACULTY OF ENGINEERING AND SCIENCE BACHELOR OF SCIENCE (HONS) BIOTECHNOLOGY YEAR 1 SEMESTER 2 UESB 1212 LABORATORY 1B THE PROPERTIES OF MATTER EXPERIMENT 5: KINETICS: THE RATES OF A CHEMICAL REACTION NAME/ID: LOW WEI SEONG 05UEB02315 HEW XIN HONG 05UEB02306 GROUP: 4 DATE: 16TH & 23RD JANUARY 2006 LECTURER: MR. TAN KONG WAI Experiment 5 Title Kinetics: The rates of a chemical reaction Objectives - To determine the rate of reaction of chemical reaction. - To study changes made to rate of reaction when there is vary in concentration and temperature. - To obtain graph concentration/temperature against rate of reaction from data collected. Introduction In this experiment, we are going to study of chemical reaction, seeing how the rate of chemical reaction varies with reactant concentration and temperature. We also are going to see how this data can give information for us about the pathway and mechanism. In Part A and Part B of the experiment you will investigate the effect of reactant concentration on the rate of reaction, and thereby obtain the rate equation. The effect of temperature is studied in Part C, and the results used to find the activation energy for the reaction. Chemical kinetics is the study and discussion of chemical reactions with respect to reaction rates, effect of various variables, re-arrangement of
Synthesis and Characterization by UV-Vis Spectroscopy, EPR, and HNMR of H2TPP and CuTPP Porphyrins
Synthesis and Characterization by UV-Vis Spectroscopy, EPR, and HNMR of H2TPP and CuTPP Porphyrins Introduction Due to their ubiquity in both enzymatic and electron transfer proteins, prophyrin ring derivatives continue to be of great interest to chemists and biochemists. Specifically, porphyrin rings are the key structural component of the active sites of hemoglobin, myoglobin, chlorophyll, vitamin B12, and mitochondrial cytochrome c (Shriver, Atkins, Overton, Rourke, Weller & Armstrong, 2006). Perturbation of the metal center in metalloporphyrins largely dictates the protein's function. The primary functions of both hemoglobin and myoglobin, porphyrin rings with iron centers, are oxygen binding and transport, whereas in chlorophyll and cytochrome c, magnesium centered and iron centered, respectively, the proteins function in an electron transfer capacity (Shriver et. al., 2006). In an effort to fully understand both the enzymatic and electron transfer properties of these, as well as other porphyrin derivatives, chemical and spectroscopic research to fully characterize hemeprotein functionality has been underway since before 1970 (Castro, 1971). In addition to their biological function, porphyrins show promise in a large number of energetic and pollution abatement processes. For example, it has been proposed that porphyrin derivatives may be of use in the following
Synthesis and Isomerization of Nitro and Nitritopentaamminecobalt(III) Chloride, Linkage isomers.
Synthesis and Isomerization of Nitro and Nitritopentaamminecobalt(III) Chloride, Linkage isomers. Abstract: In this experiment two compounds were synthesized, nitropentaamminecobalt(III) chloride and nitritopentaamminecobalt(III) chloride, which are a pair of linkage isomers. The infrared spectra of both compounds were measured to compare, and differentiate the two. Upon inspection, the nitritopentaamminecobalt(III) chloride compound had an asymmetric stretch at 1452cm-1 indicating a Co-ONO bond. Nitropentaamminecobalt(III) chloride does not have this peak, instead it has stretch at 500 - 435 cm-1 indicating a M-N bond, an asymmetric NO2 stretch at 1428cm-1 and a NO2 bend at 595cm-1. In both complexes, there's a presence of ammonia degenerate, symmetric, asymmetric and rocking vibration frequencies. The infrared spectra of a sample of nitropentaamminecobalt(III) chloride heated in an oven overnight at 110 degrees celcius and pentaamminechlorocobalt(III) chloride were also measured for comparison to the two synthesized products. The heated nitropentaamminecobalt(III) chloride showed identical results to the non heated version, except the peak intensities were slightly less. The peaks on pentaamminechlorocobalt(III) chloride were all present on the infrared spectrum of the two synthesized products. Introduction: The bent nitrite ion (NO2-) is an example of an ambidentate
Synthesis of chloropentaaminecobalt(lll) chloride
Experiment 1 (Day 2) Synthesis of chloropentaaminecobalt(lll) chloride Abstract The complex compound [Co(NH3)5Cl]Cl2 was synthesized and electrical conductance and infrared spectra were measured to characterize. The percentage yield was calculated ,91.23 % that the error of percentage yield was discussed. The molar conductivity was obtained to determine the number of ions constituting the compound which was not successful. Also, the frequencies of product were examined to observe the peak of ammonia group. Introduction In this experiment, [Co(NH3)5Cl]Cl2 was synthesized and the formation and properties of a coordination compound were studied. The experiment involved a coordination compound that is formed between electron pair donors, ligands and electron pair acceptors, the metal atoms. Generally, a coordination compound is made up of a central atom which is bound to ligands. There is many possible ligands that can bond to the central atom, but NH3 was used that donates one pair of electrons to form coordinate bonds. In the formation of chloropentaaminecobalt(lll) chloride, denoted [Co(NH3)5Cl]Cl2, the transition metal which serves as the central atom is cobalt. Since cobalt is involved in six bonds, its coordination number is six, and the structure around the cobalt is octahedral. The synthesis of cobalt(lll) complexes involved oxidation of the cobalt(lll) salt in the
Ion exchange
Chemistry 244 Experiment 4 - Ion exchange: Determination of Fe3+ and Ni2+ content Dian Page 5533670 21 September 2010 Abstract The separation of a Fe3+ and Ni2+ mixture was firstly investigated; followed by the determination of the Fe3+ and Ni2+ content (concentration) in the original mixture. It was found that iron was a yellow solution and nickel respectively had a greenish colour. Their original concentrations respectively were 0.0392M for iron and 0.00225M for nickel. Introduction Ion exchange is an exchange of ions between two electrolytes or between an electrolyte solution and a complex.1This term can be used to denote the process of separation of aqueous and other ion-containing solutions with solid polymeric or mineral ion exchangers. Typical ion exchangers are ion exchange resins, zeolites and soil humus. Ion exchangers are either cation exchangers that exchange positively charged ions or anion exchangers that exchange negatively charged ions. Amphoteric exchangers exchange both cations and anions simultaneously.2 An ion-exchange resin (refer to figure 1) is an insoluble matrix normally in the form of small beads, yellowish in colour, fabricated from an organic polymer substrate. They are capable of exchanging particular ions within the polymer with ions in a solution that is passed through them. Synthetic resins are used in various applications including
Experiment 5 - Determining Molecule Weight by Freezing Point Depression Method
Experiment 5 Title: Determining Molecule Weight by Freezing Point Depression Method. Objectives: ) To determine the freezing point of substance from its cooling curve and study the effect of foreign substance content on the freezing point of a solvent (substance). 2) To determine the molecular weight by using the freezing point depression method. Introduction: Freezing-point depression describes the phenomenon that the freezing point of a liquid (solvent) is depressed when another compound is added. This means that a solution has a lower freezing point than a pure solvent. This happens whenever a solute is added to a pure solvent, such as water. The phenomenon may be observed in sea water, which due to its salt content remains liquid at temperatures below 0°C, the freezing point of pure water. The freezing point depression is a colligative property, which is dependent on the presence of dissolved particles and their number, but not their identity. It is an effect of the dilution of the solvent in the presence of a solute. It is a phenomenon that happens for all solutes in all solutions, even in ideal solutions, and does not depend on any specific solute-solvent interactions. The freezing point depression happens both when the solute is an electrolyte, such as various salts, and a nonelectrolyte. In thermodynamic terms, the origin of the freezing point depression is
Determining Chemical Formulas
Determining a Chemical Formula Abstract: The purpose of this laboratory is to create a bond between two or more substances to determine the empirical formula of the substance. The bond that is trying to be created in this lab is magnesium oxide. By heating the magnesium and introducing water, will create magnesium oxide which massing the final product and comparing it to the original will produce the values for the empirical formula. Procedure: The procedure was taken from experiment 5 in General Chemistry by Grace R. Hered. . Clean a crucible over a Bunsen flame for five minutes and allow it to cool to room temperature. 2. Weigh the crucible, and measure a 0.3g sample of magnesium in it. 3. Heat the crucible with its contents with the cover on for about 5 minutes. 4. Use the tongs to displace the lid slightly to allow air flow, and heat strongly for 10 minutes. 5. Remove the flame and somewhat cool, and add 2-3 drops of water. 6. Heat gently and then strongly with lid slightly displaced for 5 minutes 7. Cool crucible and then weigh. 8. Record your data and calculations Data: The following data table, table 2, was created after the weights were obtained. Weight of the crucible 19.83g Weight of the crucible & Magnesium 20.12g Weight of the Magnesium 0.29g Moles of magnesium 0.011929 0.29g Mg x (1 mol Mg / 24.31g Mg) = 0.011929 moles Weight of the
Preparation of alum from scrap aluminium
Chemistry 244 Experiment 3 - The preparation of alum from scrap aluminium Dian Page 5533670 30 August 2010 Abstract The recovery of aluminium from scrap aluminium through its conversion to potash alum (KAl(SO4)2·12H2O) was investigated. It was found that a final percentage yield of 76% was obtained. In addition a final yield of 9.00g was yielded. Introduction Aluminium, because of its low density, high tensile strength and resistance and resistance to corrosion, is widely used for the manufacture of aeroplanes, automobiles, lawn furniture as well as for aluminium cans. Being a good conductor of electricity, it is used for transmission of electricity. Aluminium is also used for making utensils. The recycling of aluminium cans and other aluminium products is a very positive contribution to saving our natural resources. Most of the recycled aluminium is melted and recast into other aluminium metal products or used in the production of various aluminium compounds, the most common of which are the alums.1 Alum is a salt that is a combination of an alkali metal, such as sodium, and a trivalent metal, such as aluminium.2 & 3 Alums are double sulphates having a general formula (equation 1) of: Important types of alum and their respected formulas . Potash alum - KAl(SO4)2·12H2O 2. Soda alum - NaCr(SO4)2·12H2O 3. Chrome alum - KCr(SO4)2·12H2O Potash alum is used in
Investigation of the precision and accuracy of various analytical techniques in determining the identity and quantity of barbiturates in a mixture.
Investigation of the precision and accuracy of various analytical techniques in determining the identity and quantity of barbiturates in a mixture. Aim The aim of this investigation was to identify the barbiturates given to us in a mixture (Mixture A) and to quantify the amounts present using a variety of analytical procedures for confirmation of results. Some techniques were used for preliminary investigation. Qualitative analysis Thin layer chromatography (TLC), infra red (IR) and Raman spectroscopy were used in determining which barbiturates were present in the mixture. A melting point determination was not done however because the melting point of a mixture of compounds will be less than the melting point of the individual compounds so therefore TLC analysis An analyte migrates up a layer of stationary phase under the influence of a mobile phase, which moves through the stationary phase by capillary action. The distance moved by the analyte is determined by its relative affinity for the stationary vs. the mobile phase. The sample was spotted onto a silica plate and was run alongside samples of known barbiturates in 3 different mobile phases * Dichloromethane: acetone (9:1) * Chloroform: acetone: ammonia (9:9:2) * Propan-2-ol: chloroform: ammonia (9:9:2) The plates were exposed to ammonia vapour before using fluorescence quenching as a detection method. From
In summary, the result of the experiment shows that adding acetic acid to water will decrease the surface tension of water. As more acetic acid is added (increased concentration), surface tension will decrease even more.
MEASURING SURFACE TENSION OF AQUEOUS SOLUTIONS BY THE CAPILLARY RISE METHOD University of the Philippines, Diliman Department of Mining, Metallurgical and Materials Engineering College of Engineering ABSTRACT The capillary rise method was used to measure the surface tension of aqueous solutions of sodium chloride and acetic acid. Molar concentrations of 0.5 M and 1.0 M for each solution were tested. The results were then compared to the surface tension of pure water to observe how solute properties affect the surface tension of water. The experimental results showed that adding acetic acid solute in water lowers the surface tension of water. As the concentration of acetic acid was increased, the surface tension of water decreased even more. However, the experiment has failed to accurately show the effect of sodium chloride solutes on the surface tension of water. Nevertheless, previous studies revealed that surface tension of electrolyte solutions, such as NaCl solution, increase with increasing concentration. The experiment revealed several disadvantages of the capillary rise method, such as difficulties in firmly holding the equipment, in reading the liquid level inside the capillary, in keeping the temperature constant, and in accurately marking the liquid level with a pen. Nevertheless, the capillary rise method proved to be comparatively reliable, provided that
