Documents about Iodine Clock
Experiment 4
Tulane, CHEM 118
Excerpt: ... EXPERIMENT 4 Kinetics of the Iodine Cock reaction EXPERIMENT 4 Kinetics of the Iodine Clock reaction 4.1. Purpose In experiment 4, the rate law of the Iodine Clock reaction is established, and a value for the activation energy of the reaction is derived. 4.2. Background One of the goals in a chemical kinetics study is to derive an equation that can be used to predict the relationship between the rate or the speed of a reaction and the concentration of the reactants. Such an experimentally determined relation is called a rate law, or rate equation. If one considers a hypothetical reaction such as the one displayed in equation 4.1, aA + bB + cC + . products (4.1) then the rate of the reaction vr is often of the form as shown in equation 4.2: vr = k[A]m [B]n [C]p . (4.2) The characteristic proportionality constant k is called the rate constant of the reaction. The kinetic exponents m, n, p . are generally small, positive whole numbers, although in some cases they may be zero, or fractions ...
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Experiment 6
Cornell, CHEM 2070
Excerpt: ... Experiment6:ChemicalKinetics:IodineClockReaction By RohiniBagrodia LabInstructor:AlexanderGao February28,2008 ...
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CHEM132L
JMU, CHEM 132
Excerpt: ... CHEM 132 LABORATORY SCHEDULE* Fall 2006 Date Aug. 28 - 30 Sept. 4-6 Sept. 11-13 Sept. 18-20 Sept. 25-27 Oct. 2-4 Oct.9-11 Oct. 16-18 Oct. 23-25 Oct. 30 Nov. 1 Nov. 6 - 8 Nov. 13-15 Nov. 20-22 Nov. 27-29 Dec. 4-8 Dec. 11-13 Experiment Check in Lecture: Safety, Grading and Lab Reports Experiment 12: Spectrophotometric Analysis of Commercial Aspirin Experiment 16: Determination of an Equilibrium Constant (Part I) Experiment 16: Determination of an Equilibrium Constant (Part II) Experiment 14: Le Chatelier's Principle in Iron Thiocyanate Equilibrium Experiment 18: Weak Acids, Bases and their Salts Problem Session or Test Experiment 19: Determination of the Ionization Constant of a Weak Acid Experiment 20: Investigation of Buffer Systems Experiment 21: Determination of Acid Neutralizing Power of Commercial Antacids Experiment: The Solubility of Potassium Bitartrate Thanksgiving week Experiment 15: A Kinetic Study of an Iodine Clock Reaction Final Test Exam Week pp. 133 - 139 pp. 169 - 177 pp. 179 - 185 pp.187-19 ...
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Quizschedule.08
Georgetown, STATS 040
Excerpt: ... olubility rules, strong vs. weak electrolytes, driving forces. Exp 21A & worksheet. Know solubility rules, strong vs. weak electrolytes, driving forces. Exp 15 and worksheet. The activity series will be given. Oct 14-17 Oct 21-24 Calorimetry 7 Exp 28 and worksheet. More practice with Ch. 5 49-58. Oct 28-31 Photoelectric effect, atomic spectra, e- configurations No Quiz Lewis electron dot structures VSEPR theory & hybrid orbitals 8 Atomic Spectra experiment and Ch. 6 129, 30, 31-38, 67, 71, 73 Nov 4-7 Nov 11-14 9 8.5-8.7 in text, 45-56, 60-64 Exp 11 and Ch. 9 21, 25, 35, 47, 55, 56 Gas Laws Lab and Ch. 10 15, 29-51 odd Nov 18-21 Nov 25-28 Dec 2-5 Gas laws: Boyles law, Charles 10 law, Ideal gas law No Quiz Kinetics 11 Iodine clock lab, Ch. 14 13, 19, 2333 odd, 86, 92 ...
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IodineClockNew
California State University, Monterey Bay, CHEM 104
Excerpt: ... Name:_ Section_ Chemistry 104 Laboratory University of Massachusetts Boston IODINE CLOCK REACTION KINETICS PRELAB ASSIGNMENT Calculate the initial concentration of H2O2 that exists immediately after mixing together the contents of vessels A, B and C as specified for RUN 1 on page 2. The volume of 2 drops of starch is negligible. Answer_ INTRODUCTION In this experiment we will determine the effect of a reactant concentration and temperature on the rate of a chemical reaction. A reaction is chosen which proceeds conveniently slowly near room temperature and which can be measured easily by a dramatic color change. This reaction is the oxidation of iodide ion (I-) to molecular iodine (I2) by hydrogen peroxide (H2O2): slow H2O2 + 2 H + + 2 I I2 + 2 H2O (1) As this reaction proceeds, the colorless reactants gradually develop a brown color due to the product I2. Because of the difficulty of timing the appearance of the I2, we make use of ...
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labschedule
St. Francis IL, CHEM 302
Excerpt: ... FIRST WEEK OF LAB January 12/13. Make-up lecture. Computer Lab: Kinetics, Quantum Mechanics and 3-D plots. (handout) ENZYM E KINETICS #x1 Enzyme Kinetics (handout) Monday lab held on January 20, 2008 (a calendar Tuesday) Tuesday lab held on April 14, 2008 (can attend Jan 20) SCHEDULE FOR EXPERIM ENTAL LABORATORY PROJECTS #20 #22 #23 #34 Method of Initial Rates: Iodine Clock Inversion of Sucrose Kinetics of the Decomposition of Benzendiazonium Ion Absorption Spectra of Aromatic Dyes page 247 page 264 (plus handout) page 275 page 378 Note: You will prepare your own solutions. See handout for the preparation of the starch solution. W e will not do the "Flowing Clock Modification" Note 1. W e will use different dyes than the ones listed in the book. Each group will have a different set of dyes, see below, you will also be responsible for finding the chem ical structure of each dye before you com e to the lab. The nam es in parenthesis are alternative nam es of the dyes you will use. Groups 1, 5: Coum arin 450 ...
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instructorguide
UPenn, CHEM 506
Excerpt: ... Kinetic s Lab Instructors Guide Iodine Clock Reaction The Iodine Clock Reaction is a versatile lab that can be used to demonstrate a variety of chemical concepts. This version is used primarily to stress collision theory and its significance in the rate at which reactions occur. Preparation of Lab materials The following preparation guide is enough for a standard set of 30 students working in groups of two. However, it is recommended that the Pre-lab and Post-lab POGIL activities be done in groups of 4 or 5 in order to facilitate a better understanding of the concepts. 1 liter 0.20 M KI (potassium iodide) Dissolve 33.20 grams of KI into 500 mL of DI H 2O, dilute to 1 Liter in a volumetric flask 2.0 liter 0.100 M (NH 4) 2S2O 8 (ammonium peroxydisulfate) Dissolve 22.82 grams of (NH 4)2S2O8 (ammonium peroxydisulfate) into 500 ml of DI H 2O, dilute to 1 Liter in a volumetric flask. Transfer to a container and repeat 1 liter 0.0050 M Na 2S2O 3 (sodium thiosulfate) Dissolve 1.24 grams of Na 2S2O3 * 5H 2O (sodium th ...
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Fridayiodineclock
Oklahoma Baptist, CHEM 105
Excerpt: ... Friday iodine clock Group 1 2 3 4 5 6 7 8 1.000 2.000 3.000 4.000 5.000 6.000 7.000 8.000 Total Volume 60.000 80.000 100.000 140.000 120.000 150.000 160.000 180.000 RT Time 15.000 28.000 51.000 176.000 100.000 175.000 213.000 270.000 Low Temp Time 53.000 59.000 127.000 281.000 240.000 275.000 417.000 470.000 Mon, Sep 23, 2002 9:35 AM Data from "Friday iodine clock " 300 y = 4.0121 * 10^(1.0861e-2x) R^2 = 0.968 200 RT Time 100 0 50 100 150 200 Total Volume Data from "Friday iodine clock " 500 y = 16.161 * 10^(8.5773e-3x) R^2 = 0.947 400 Low Temp Time 300 200 100 0 50 100 150 200 Total Volume ...
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Fridayiodineclock
Oklahoma Baptist, CHEM 106
Excerpt: ... Friday iodine clock Group 1 2 3 4 5 6 7 8 1.000 2.000 3.000 4.000 5.000 6.000 7.000 8.000 Total Volume 60.000 80.000 100.000 140.000 120.000 150.000 160.000 180.000 RT Time 15.000 28.000 51.000 176.000 100.000 175.000 213.000 270.000 Low Temp Time 53.000 59.000 127.000 281.000 240.000 275.000 417.000 470.000 Mon, Sep 23, 2002 9:35 AM Data from "Friday iodine clock " 300 y = 4.0121 * 10^(1.0861e-2x) R^2 = 0.968 200 RT Time 100 0 50 100 150 200 Total Volume Data from "Friday iodine clock " 500 y = 16.161 * 10^(8.5773e-3x) R^2 = 0.947 400 Low Temp Time 300 200 100 0 50 100 150 200 Total Volume ...
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rate of chemical reactions
Winona, COURSE1 1
Excerpt: ... the concentrations of reactants and possibly other substances like catalysts. The dependence of the rate on concentration is represented by a rate law, which usually has the following form: Rate = k [A]a [B]b [C]c where k is the rate constant, the value of which must be determined experimentally, and the superscripts are called the order with respect to that particular substance. Your team will be studying the " iodine clock " reaction, a reaction commonly used to demonstrate the dependence of rate on concentration. In this reaction, potassium iodate (KIO3) and sodium hydrogen sulfite (NaHSO3) react with each other, producing elemental iodine as shown below. 5 HSO3-(aq) + 2 IO3-(aq) I2(s) + 5 SO42-(aq) + H2O(l) + 3 H+(aq) This is an oxidation-reduction (redox) reaction in which iodine(V) is reduced to iodine(0) and sulfur(IV) is oxidized to sulfur(VI). Because elemental iodine is colored (pale yellow) and the other reactants and products are colorless, the rate of reaction can be monitored simply by observi ...
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exp16_RSW
Colgate, CHEM 102
Excerpt: ... Experiment 16-077b Iodine-Clock Reaction Name _ I Reaction Rate Data Run 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. [S2O82-] (M) _ _ _ Date _ Section _ [S2O32- ] (M)for all mixtures _ [I-] (M) _ _ _ Time (sec.) _ _ _ _ _ _ _ _ _ _ _ _ _ _ Rate ...
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chem 211 lab report 8
Cornell, CHEM 211
Excerpt: ... Lab 8: Chemical Kinetics: Iodine Clock Reaction Purpose: The purpose of this investigation was to determine the rate at which the following reaction occurs: Procedure: The team designed and performed experiments in order to determine the complete concentration and temperature dependence of the reaction rate for the reaction of peroxydisulfate ion and iodide ion in aqueous solution. The team ran five trials mixing different amounts of KI, S2O3, S2O8, and H2O and recorded the time it took for the reaction stated above to occur. This time recorded was the time it took for the mixture to turn a dark blue color, which occurs when peroxydisulfate is mixed with iodide in the presence of starch and thiosulfate. One of the trials was preformed at a different temperature. The team then calculated the concentrations of each chemical present in each reaction, the reaction orders with respect to peroxydisulfate and iodide, the temperature specific rate constant for the two temperatures used, and the frequency factor ...
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iodine_clock_rxn_handout
WVU, PCHEM 20
Excerpt: ... Pre-lab Questions Exp. 20 Iodine Clock Reaction 1. Calculate the molar concentration of hydrogen peroxide (31.5%). 2. Calculate how to dilute the above solution to 0.1 M H2O2 (250 ml). 3. Calculate how to dilute the 0.1 M HCl solution to 0.01 M HCl (250 ml). 4. Draw a table to write down the experimental data. There are 4 sets of experiments, for each set, you should get 3 results which are close to each other. You may need 4 or 5 trials to get them if you are not lucky. 5. Use the reaction time of first experiment as the reference, what should we expect for each set of experiment in terms of the reaction time, same, double or .? ...
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laboratory_schedulespring2005
California State University, Monterey Bay, CHEM 104
Excerpt: ... Laboratory Schedule Spring 2005 Week of Jan 30 Feb 6 Feb 13 Feb 20 Feb 27 March 6 March 13 March 20 March 27 April 3 April 10 April 17 April 24 May 1 Title of Experiment Stoichiometry - Limiting Reagents Boyles Law Quantitative Analysis of Ions Week of Presidents Day - no labs Hexamine Nickel (II) Chloride Synthesis Hexamine Nickel (II) Chloride Analysis Spring Vacation- no Labs Iodine Clock Reaction Kinetics An Equilibrium Constant Determination pH Measurements and Titration Buffer Solutions Week of Patriots Day- no Labs An Electrochemistry Experiment Lab # 1 2 3 4 5 6 7 8 9 10 ...
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Chemical Kinetics
Cornell, CHEM 2080
Excerpt: ... Chemical Kinetics: Iodine Clock Reaction By Kolene McDade TA: Steve Hickman September 26, 2007 I. Abstract: By measuring the time it took to produce a specific amount of I 2 from the reaction of potassium iodide and peroxydisulfate, the rate of this reaction could be measured. From this data and by the variation of the volumes of the reactants in three different trials at one temperature and one trial at a higher temperature, the orders of the reactants could be experimentally determined. From that, the temperature dependent rate constants were determined to be 5.59E-02 M-1s-1 at 293 K and 1.64E-02 M-1s-1 at 311 K. These two rate constants were used in a formula, derived from the Arrhenius equation, to determine the activation energy for this reaction. It was experimentally determined to be 51.6 KJ/mol. II. Introduction: The reaction of the peroxydisulfate ion with the iodide ion in an aqueous solution was analyzed to study the chemical kinetics of reactions. The following is the equation for such a rea ...
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012309
USC, CHEM 105BLG
Excerpt: ... Reactions with More Than One Reactant For the reaction: BrO3- (aq) + 5 Br- (aq) + 6 H+ (aq) 3 Br2 (l) + 3 H2O (l) Rate = -[BrO3-]/t = k[BrO3-][Br-][H+]2 to find k, take an experiment where the concentrations of two of the reactants are much higher than the other reactant, can find k and solve for k Reactions with More Than One Reactant For the reaction: BrO3- (aq) + 5 Br- (aq) + 6 H+ (aq) 3 Br2 (l) + 3 H2O (l) Rate = -[BrO3-]/t = k[BrO3-][Br-][H+]2 find k when [H+]o = 1.00 x 10-4 M, [Br-]o = [BrO3-] = 0.500 M and after 9.5 s [H+] = 5.00 x 10-5 M Integrated Rate Law: Summary Iodine Clock Reaction Time (s) mL NaIO3 5.0 7.5 10.0 12.5 15.0 ln (mL NaIO3) 1/(mL NaIO3) What do you think is the order of the iodine clock reaction? 0 2. 1 3. 2 1. 82% 14% 3% 0 1 2 Rate Definition Rate Definition Reaction Mechanism Reaction Mechanism the series of steps taken for a reaction to take place Intermediate any substances that is produced in one step and consumed in a later step a ...
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IodineClock_RF
Wilkes, CHM 114
Excerpt: ... A KINETIC STUDY OF AN IODINE CLOCK REACTION Name: Course: Date Expt. Performed: Partner: Purpose (50 words or less): Spreadsheets, Graphs, and Calculations: Instructions: complete the following data table, then construct the two graphs, log rate vs. log concentration of reactant. When that is done complete the rest of the form as instructed below. Calculations can be done in a spreadsheet, but arrange the spreadsheets like following tables! Data Table 1 Calculation of data needed to construct graphs. Trial 1 2 3 4 5 Show calculation of [S2O32-], rate, log rate, [KI] log [KI], [S2O82-], and log [S2O82-] for trial one here. ave. time sec [S2O32-] M ave. Rate M/sec Log Rate [KI] M log [KI] [S2O82-] M log [S2O82-] 1 What is notable about the concentration of thiosulfate in each trial? Which three trials will be used to determine m? Which three for n? Find the slopes of the two graphs to find the values of m and n. Show the slopes calculations below unless you have used a spreadsheet to fit the data (in tha ...
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Chem1230FinalKEY_V6
Wayne State University, CHM 1230
Excerpt: ... 5 degC DT Kf 0.129268 molal c. The solute was dissolved in 25.58 g of solvent. How many moles of solute are in the solution? cm n wtSolvent n cm wtSolvent 0.129 Mole Kilogram 1000 Gram Kilogram 25.58 Gram n cm wtSolvent 0.00329982 Mole d. If the mass of the solute is 0.3506 g, what is the molar mass of the solute? MW MW wt moles wt moles 0.3506 Gram 0.00330 Mole 106.242 Gram Mole 4 Chem1230FinalKEY_V6.nb 14. The iodine clock You are studying the rate of the reaction: Some rate data has already been collected: (different table in each version) 2 A + B |> C + 3D a. Write the general formula for the rate law of this reaction. b rate = k @ADa @BD , where a and b are small integers k rate1 c@A1Da c@B1Db c@A1D c@A2D a b. The order of which reactant be determined from these data? What is the order? = rate2 c@A2Da c@B2Db b rate1 rate2 LogB c@B1D c@B2D c@A1D c@A2D LogA LogA = F c@A1D c@A2D a since c@B1D c@B2D rate1 rate2 a ...
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Chemlab4
University of Maine, CHY 123
Excerpt: ... CHY 123 Chemical Kinetics: Iodine Clock Experiment Introduction To determine the rate law for a reaction we must understand how the speed of a reaction can be determined and the affects of concentration on the rate of a reaction. Many different factors (such as temperature) affect the speed of a reaction. This overall process can be summed up as chemical kinetics. The study of chemical kinetics can be used to compare reactions such as crystal formations or of explosions. Procedures We gathered the needed chemicals and containers needed for the experiment. We first tried many different combinations of the chemicals in the small reaction plate and recorded to different reactions and what occurred after each mixture. After we had used all the combinations that we could think of we then worked on calculating the initial concentrations of the reactants that we would be using in this experiment. Afterward, we filled an Erlenmeyer flask with 10.0 mL of KI, 1mL of starch solution, 1.0 mL of Na2S2O3 and 20.0 mL ...
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Iodine Clock Reaction
Cornell, CHEM 342132
Excerpt: ... Iodine Clock Reaction By Lionel Sims III Lab Instructor: Anund February 29, 2008 Results and Discussion: This lab was done with the intention of determining the complete concentration and temperature dependence of the reaction rate for a reaction between peroxydisulfate ion and iodide ion in an aqueous solution. Substances with known concentrations were mixed in a beaker with a magnetic stirrer and had the amount of each chemical and temperature of the mixture changing between each individual trial. The chemicals used were 0.16M KI(aq), 0.12M (NH4)2S2O8(aq), 0.0055M Na2S2O3(aq), 0.10 M EDTA(aq), distilled water, and a solid soluble starch indicator. The starch is an indicator that will turn the mixture a dark blue to make the reaction visually traceable. Two reactions will be taking place in the beaker. The first will produce iodine, and the second involves the reaction of iodine with thiosulfate, which will turn the iodine back into the iodide ion that it came from, allowing the first reaction to h ...
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chem213b.Midterm.sp07
N. Illinois, CHEM 213
Excerpt: ... f water at (a)20NC (b) 80NC. (5 pts.) 3. A saturated solution of NaCl contains 9 g of salt dissolved in 20 g of water at 60oC.What is the solubility of NaCl (in g salt/100 g solvent). (6 pts.) Lab 2. Colligative Properties of Solutions 1. Explain why a 0.100 m solution of HCl dissolved in benzene has a freezing point depression of 0.512oC, while a 0.100 m solution of HCl in water has a freezing point depression of 0.352 oC. (5 pts.) 2. Calculate the number of moles of Fe(NO3)3 required to increase the boiling point of 100 g of water to 107C. The Kb for water is 0.52C/m (Hint: what is the value of i?) (8 pts.) Lab 3. Kinetics of Iodine Clock Reaction 1. Sketch the graph that was used for the determination of the activation energy, including appropriate labels for the axes. Describe how the activation energy was determined from the plot. (6 pts.) 2. During reaction #4 we had beakers A and B filled with the following solutions: Beaker A: 20mL KI and 10mL Na2S2O3 Beaker B: 5mL K2S2O8 ...
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I2kin
N.E. Illinois, CHEM 212
Excerpt: ... CHEMICAL KINETICS The Iodine Clock This experiment is concerned with chemical kinetics. The rate of a chemical reaction will be measured, and the factors that affect the rate of reaction will be studied. The reaction being studied is the oxidation of iodide ion by hydrogen peroxide in acidic solution 2I-(aq) + H2O2(aq) + 2H+(aq) I2(aq) + 2H2O (eq 1) The iodine produced by this reaction strongly interacts with excess iodide ion, which keeps the iodine soluble in water. The factors that affect the speed of the reaction are shown in the rate law. The rate law for the reaction in equation 1 takes the general form rate = -d[H2O2]/dt = k[I-]x[H2O2]y (eq 2) To determine the rate law, we must measure three unknowns in equation 2: k, the rate constant, which depends on temperature x, the order with respect to iodide ion y, the order with respect to hydrogen peroxide For the reaction in equation 1, as with most, but not all, chemical reactions, the rate does not depend on the concentration of the products. The o ...
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Chemical Kinetics
Cornell, CHEM 2080
Excerpt: ... Chemical Kinetics: Iodine Clock Reaction By Julian Remouns Lab Instructor: Bob Neumann February 22, 2008 Results and Discussion: The complete concentration and temperature dependence of the reaction rate for the reaction between peroxydisulfate ion and iodide ion in aqueous solution was determined. The following rate equation was used to find the rate of each trial at 23 C: Rate = [I ]/ t = (1/2) [S O ]/ t An example of this calculation using data from trial #1 follows: Rate= (0.5)(.0011M)/210s= 2.62 x 10^-6 M/s The data and results were tabulated: Concentrations and Rates at 23 C [S O ] (M) Trial 0.012 1 0.022 2 0.027 3 Using a system of rate laws for each trial, Rate = k[I ] [S O ] the rate constant k, and the x and y powers were found to be 0.002, 1 and 1, respectively. The temperature dependence was determined by using the Arrhenius equation, K= Ae^(-E /RT) And the data in the following table: Concentrations and Time of Reaction in 32 C Warm Water Bath [S O ] (M) [I ] (M) Time (s) Trial 0.027 0.035 13 ...
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