...Ch. 15: Kinetics 15.1 15.2 15.3 15.4 15.5 15.6 15.7 15.8 15.9 Week 15 Reaction Rates Rate Laws Forms of Rate Laws Integrated Rate Law Rate Laws: A Summary Reaction Mechanisms Steady-State Approximation A Model for Chemical Kinetics Catalysis CHEM 1310 - Sections L and M 1 Reaction Rates: Example Recap: Avg. Reaction rate = +∆[Product]/∆t Avg. Reaction rate = -∆[Reactant]/∆t Butane, C4 H 10, burns in oxygen to give CO2 and H2 O vapor. If the butane concentration is decreasing at a rate of 0.20 M/s, what is the rate at which the oxygen is decreasing? What is the rate at which the products are increasing? 2C4H10(g) + 13O2(g) Week 15 8CO2(g) + 10H2O(g) 2 CHEM 1310 - Sections L and M Reaction Rates: Example Butane, C4 H 10, burns in oxygen to give CO2 and H2 O vapor. If the butane concentration is decreasing at a rate of 0.20 M/s, what is the rate at which the oxygen is decreasing? What is the rate at which the products are increasing? 2C4H10(g) + 13O2(g) 0.20 M/s For oxygen: 0.20 mol C4 H 10 Ls Week 15 8CO2(g) + 10H2O(g) ? ? ? x 13 mol O2 2 mol C4 H 10 CHEM 1310 - Sections L and M = 1.3 M O2 /s 3 1 Reaction Rates: Example Butane, C4 H 10, burns in oxygen to give CO2 and H2 O vapor. If the butane concentration is decreasing at a rate of 0.20 M/s, what is the rate at which the oxygen is decreasing? What is the rate at which the products are increasing? 2C4H10(g) + 13O2(g) 0.20 M/s For CO2: 0.20 mol...
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...Enzyme Kinetics: Inversion of Sucrose Abstract Enzymes are a class of proteins that catalyze practically all biochemical reactions. The enzymatic reactions were looked at by the use of two comparable reactions of enzyme invertase and a acidic form of the reaction. The order of the nonacidic enzymatic reaction was zero order due to substrate concentration and due to the fact that the reaction was time dependent. It is also due to having large R2 value at 0.9932 for D run and a smaller R2 value at 0.9902 for C run. The acidic runs had a first order reaction, which had a lower R2 values at 0.9028 for run D and 0.9028 for run C. Also, the percent error in run C at 33.31% was found to be much lower than the percent error in run D at 55.77%, which mean the concentration of run C is more effective than run D. I. Introduction In this experiment the chemical kinetics of the enzyme catalyzed inversion of sucrose was studied. The reaction that we will study in this experiment is the inversion of sucrose, catalyzed by the enzyme invertase that is derived from yeast: The rate of reaction of this reaction was compared to the same reaction that is to be catalyzed by hydrogen ions. Enzymes make up an important class of proteins that are used to catalyze a wide array of biochemical reactions. The enzyme that was used to catalyze the reactions in this lab experiment was the enzyme...
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...Introduction: In this experiment, the rate law and rate constant for a reaction of oxalic acid with permanganate were determined. Every chemical reaction ranges from hours to femtoseconds to occur. The rate of a chemical reaction can be determined by assessing the change in either the reactant or product in a given time or point (Connors, 1990). It is important to take account of the stoichiometric ratios of each component, regardless as to which compound is chosen to determine the rate. The study of the rates of chemical reactions is called Chemical Kinetics (Soustelle, 2011). The following is an example of a generic chemical reaction: aA + bB → cC + dD The rate of the reaction can be expressed as a function of each reactant and each product: Rate = -1a∆A∆t= -1b∆B∆t= +1c∆C∆t= +1d∆D∆t For each reaction, the concentration is decreasing as the reaction occurs; therefore representing the rate as a positive value and a negative sign in the rate definition is used. The concentration of the products is conversely increasing as the reaction proceeds; therefore changing in concentration is positive (Connors, 1990). The reaction rate can be measured by accurately measuring the change in concentration of one of the reaction species over time. This experiment utilized a visual change in color of one of the reactants used; however, since visual indications can be subjective and it is important to perform the experiment multiple times. Also, since the color change would indicate that...
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...Assignment: SCI103 Phase 5 Lab Report TITLE: Potential and Kinetic Energy INSTRUCTIONS: Enter the Virtual Lab and conduct the experiments provided. Please type your answers on this form. When your lab report is complete, submit it to the Submitted Assignments area of the Virtual Classroom. Part I – Answer the following questions while in the Phase 5 lab environment. Section 1 – From the left of the screen to the right, the red balls have a center of mass placed at 20 feet, 15 feet, and 10 feet high respectively. 1. Suppose each red ball weighs 20 lbs. Find the potential energy (PE) for each ball on each ramp. In this lab mass is given in pounds and height is in feet, so use 32.2 ft/sec2 as the gravitational constant. Your answer will be in foot-pounds since US units are being used. PE = m g h where g = 32.2 ft/sec2 Ramp 1: Potential energy is 541.21 Ramp 2: Potential energy is 406.21 Ramp 3: Potential energy is 271.10 2. Predict the maximum speed (velocity) of each ball on each ramp. How would this speed change if each ball’s mass was doubled? ASSUMPTION: assume there is no friction and that all the potential energy you calculated in question 1 is transformed into kinetic energy – PE = KE. Use the following equation. KE= ½ m v2 You want to calcu-late v maximum speed v = [KE/ ½ m]½ This means divide the KE by half the mass and then take the square root. Max v for 20 lb. ball Max v for 40 lb. ball Ramp 1 25.38 17...
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...Second Order Reaction Kinetics Abstract The objective of this experiment was to determine if the specific rate constant of the reduction reaction of hexacyanoferrate (III) ion with ascorbic acid (C6H8O6) is affected by the ionic strength of the solution and the charges of the ion species within the solution. A Cary Bio 50 Spectrophotometer and its associated software was used to measure the absorbance of the solution at a wavelength of 418 nm. Analysis of the data collected supports the conclusion that the ionic strength of the solution and the charges of ions on the activated complex have a direct relation to the rate constant. The experimental value of 2.237 for the ionic strength of 0.025 M when compared to the literature value of 1.72 in a similar experiment by Nobrega and Rocha, has a percent error of 30%. For the ionic strength of 0.05 M, the percent error between the experimental value 2.851 and the literature value of 2.58 was 11%. The ionic strength of 0.1 had an error of -1% between the literature value of 3.97 and the experimental value 3.924. For the ionic strength of 0.2 there was a -23% error between the experimental value of 5.301 and the literature value of 6.89 (Nobrega, 1997). The experimental value of the product of the charges of the ions in the activated complex, 2.1, was lower than the expected value 3, which could be due to the shielding of the charges on the reactants due to the ions witihin the solution. Introduction The reduction of the hexacyanoferrate...
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...Kinetics by the Initial Rates Method Introduction Rate laws are mathematical expressions that describe the relationship between reactant concentrations and the rates of reaction, taking the form, Rate = k[reactant 1]m[reactant 2] n[reactant 3]p… [M/s] (1) The proportionality constant k is the rate constant; any given reaction has a specific value of k for a given set of conditions, such as temperature, pressure, and solvent; the rate constant, in contrast to the rate of reaction, does not depend on the concentration of the reactants. Exponents m, n, p, …, are the reaction orders, and indicate the degree to which the reaction rate depends on the concentration of the associated reactant. “There is no simple correlation between the stoichiometry of the reaction and the rate law”; the reaction orders, and thus the rate constant, must be determined experimentally, as in this experiment between acetone (CH3COCH3), the hydronium ion (H3O+), and iodine (I2), called the iodination of acetone. The reaction in this experiment is shown in Figure 1 and Eq.2.2 Figure 1. Reaction of acetone, iodine, and hydronium ion. CH3COCH3 (aq) + I2 (aq) CH3COCH2I (aq) + HI (aq) (2) Thus, the rate law in this experiment is shown in Eq. 3. Rate = k[CH3COCH3]m[H3O+] n[I2]p (3) The reaction rate expressions are shown in Eq. 4. Rate = -Δ[CH3COCH3]/Δt = -Δ[H3O+]/Δt = -Δ[I2]/Δt (4) Spectrophotometry can be used here to measure the reaction rate expressed as the disappearance...
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...Purpose: To determine the kinetics of the acid-catalyzed reaction of bromine and acetone via initial rate measurements and isolation method in order to approach the reaction mechanism. Data and discussion: The initial reaction of the production of brominated acetone can be written as: CH3COCH3 (aq)+ Br2 (aq) ---→CH3COCH2Br(aq) + Br– (aq) + H+ (aq) Data table Trial | Saturated Br2 solution (mL) | Acetone(mL) | 1.00 M HCl(mL) | Initial rate(abs/min) | [Ac](M) | [HCl](M) | Mole/L Br2 reacting per min per liter | Rate constant(M-1 min-1) | 1 | 3 | 5 | 10 | 0.0060 | 0.681 | 0.1 | 1.11 E-4 | 1.72 E-3 | 2 | 6 | 5 | 10 | 0.0060 | 0.681 | 0.1 | 1.17 E-4 | 1.72 E-3 | 3 | 9 | 5 | 10 | 0.0120 | 0.681 | 0.1 | 1.59 E-4 | 2.33 E-3 | 4 | 9 | 5 | 5 | 0.0120 | 0.681 | 0.05 | 1.60 E-4 | 2.33 E-3 | 5 | 9 | 5 | 20 | 0.0240 | 0.681 | 0.2 | 3.01 E-4 | 4.57 E-3 | 6 | 9 | 10 | 20 | 0.0480 | 1.362 | 0.2 | 6.23 E-4 | 1.10 E-3 | 7 | 9 | 20 | 20 | 0.0900 | 2.742 | 0.2 | 1.79 E-4 | 3.22 E-3 | The concentration of the saturated bromine solution was determined by diluting and measuring the absorbance of the solution at 450 nm .Distilled water was used as blank. The Beer’s law was then used to determine the concentration of bromine solution. Abs =ЄCl Where, Abs=0.288 and l= 1 cm and Є is the extinction coefficient or molar absorption coefficient = 100 (M-1 cm-1). So concentration of bromine solution was calculated using 1:100 dilution. To determine the initial rate, Abs...
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...When roller coaster start to elevate up it uses an engine. Once it reaches the top it stops and turns to potential energy, because it is still and getting ready to fall. When the coaster falls it turns into kinetic energy, because it’s in motion. From the on the coaster doesn’t need an engine. The gravity takes it down the coaster in a large amount of speed. Then the speed that can go up to like 60 mph will keep the roller coaster going even if it is going up a hill or down the speed is strong enough to take it all the way. The energy will stay for a while, but roller coasters aren’t too long. You may wonder why roller coasters aren’t too long because the energy will start to fade and the roller coaster will slow down and eventually come to...
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...Experiment 5 Enzyme Kinetics: The Effect of Yeast Alcohol Dehydrogenase and Coenzyme on the Rate of Oxidation of Ethanol. Results Raw data: Effect of Enzyme Concentration | Reagent | 1 | 2 | 3 | 4 | Buffer B | 2.5 ml | 2.4 ml | 2.3 ml | 2.2 ml | NAD+ | 200 μl | 200 μl | 200 μl | 200 μl | Dilute ADH | 200 μl | 300 μl | 400 μl | 500 μl | 6 M Ethanol | 100 μl | 100 μl | 100 μl | 100 μl | Time 0 sec. | 0.022 | 0.026 | 0.069 | 0.073 | Time 5 sec. | 0.028 | 0.038 | 0.110 | 0.114 | Time 10 sec. | 0.038 | 0.051 | 0.141 | 0.150 | Time 15 sec. | 0.048 | 0.064 | 0.176 | 0.187 | Time 20 sec. | 0.058 | 0.078 | 0.206 | 0.222 | Time 25 sec. | 0.068 | 0.091 | 0.239 | 0.259 | Time 30 sec. | 0.078 | 0.104 | 0.270 | 0.291 | Time 35 sec. | 0.088 | 0.115 | 0.301 | 0.325 | Time 40 sec. | 0.099 | 0.131 | 0.331 | 0.358 | Time 45 sec. | 0.109 | 0.145 | 0.362 | 0.391 | Time 50 sec. | 0.119 | 0.158 | 0.392 | 0.424 | Time 55 sec. | 0.130 | 0.167 | 0.420 | 0.455 | Time 60 sec. | 0.140 | 0.179 | | | Effect of Coenzyme(NAD) Concentration | Reagent | 1 | 2 | 3 | 4 | Buffer B | 2.4 ml | 2.35 ml | 2.3 ml | 2.25 ml | NAD+ | 10 μl | 50 μl | 100 μl | 150 μl | Dilute ADH | 500 μl | 500 μl | 500 μl | 500 μl | 6 M Ethanol | 100 μl | 100 μl | 100 μl | 100 μl | Time 0 sec. | 0.009 | 0.020 | 0.032 | 0.102 | Time 5 sec. | 0.015 | 0.038 | 0.049 | 0.152 | Time 10 sec. | 0.023 | 0.056 | 0.068 | 0.190 | Time 15 sec. | 0.029 | 0.072 | 0.088 | 0.229 | Time...
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...David D'Alleva September 24, 2013 “Free Fruit For Young Widows” By Nathan Englander (Question 1) This short story is about Shimmy Gezer and his son Etgar. Shimmy Gezer had a fruit stand in Jerusalem and his son worked with him when he wasn't in school. Shimmy had once been a soldier for the Israeli Army with his friend Tendler who now became Professor Tendler. During the story, Etgar tries to understand why his father never allows Professor Tendler to pay for his groceries each time he comes to the fruit stand. “After Etgar weighed the tomatoes and the cucumbers, his father would take up the bag, stick in a nice fat eggplant, unasked, and pass it over to Professor Tendler” (Englander 32). Shimmy would also give free products to the widows of Israeli soldiers who had died during battle. As the story progresses, Etgar's character changes, and he understands the true motivations behind his father's relationship with Professor Tendler. “Etgar wasn't one of the gray. He was a tiny, thoughtful, bucktoothed boy of certainties” (Englander 33). We have this image of Etgar as being a good innocent boy trying to understand why his father treated Tendler so good, considering Tendler's actions during the war. Tendler had murdered innocent people and had gave Shimmy such a beating while they were at war, that Shimmy still could feel the flattened bones on his face. “It was not his father's act of forgiveness but his kindness that baffled Etgar” (Englander 33). Etgar also tries...
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...In this lab we were examining how the elastic kinetic energy of a spring is affected by the distance the spring is stretched. During our experiment we experienced two problems. The first was easily resolved, because it dealt with how we were going to attach the spring to both carts in a fixed position. To fix this issue, we opted to hold the spring in place, with our hands, on the stationary cart until the other cart was released. This prevented the spring from falling off of the stationary cart until after impact with the other cart. The other problem we faced was a little more tricky, because we were not sure how to keep the stationary cart in place when the moving cart struck it. Our solution to this problem was simply to hold the cart in...
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...Coefficient of Kinetic Friction and Surface Area Purpose To investigate the coefficient of friction with respect to surface area and the applied force in contact with the sliding force. Subject/Grade Level Physics/Grades 10-12 Questions to Probe Will increasing the load (FN) effect the kinetic friction (Fk)? Will increasing or decreasing the surface area of contact effect the kinetic friction? Concept Friction arises from the electromagnetic interaction between atoms of any bulk state of matter; solid, liquid, or a gas. When the surfaces of two objects are in contact, molecules on the surface of one object are attracted to molecules of the other object. Objects that may appear very smooth to us like a table top, however, on the molecular level have many peaks and valleys. When the surface of one of the object begins to move we call this interaction kinetic friction or sliding friction. Static friction is the friction when both objects are at rest. Sliding friction is less than static friction because when both objects are at rest the molecules have time to press together in the peaks and valleys. Sunshine State Standards (SC.C.2.3) The student understands that the types of force that act on an object and the effect of that force can be described, measured and predicted. (SC.H.3.3) The student understands that science, technology, and society are interwoven and interdependent. Materials 3 wood blocks 25cm in length force scale (spring scale) screw...
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...The Relationship between Gravitational Potential Energy on Kinetic Energy at Various Locations of a Roller Coaster Respectfully Submitted to the Science Department Of Blanche Ely High School Gavin Frater Dr. Pedro Torres Anatomy and Physiology Period:1 Abstract Table of Contents 4.………………………………………………………………………………… Introduction 8………………………………………………………………………………….. Hypothesis 8………………………………………………………………………………….. Materials 8…………………………………………………………………………………... Procedures 10…………………………………………………………………………………. Results 11………………………………………………………………………..Discussion/ conclusion 12………………………………………………………………………………… Bibliography 13………………………………………………………………………………… A. Appendix Slowly, and sometimes, ever so slowly, a train of cars are being pulled up to the highest point of the roller coaster. Of course, one by one, the cars are pulled downhill until gravity takes over and push it all across the tracks. The way the roller coaster goes around is one of the best examples of how the conversion of gravitational potential energy to kinetic energy from the highest points. As the cars go up the track, it is acquiring the potential energy until the cars are at the highest point of the track. At this point, the cars have reached its maximum gravitational potential energy. Next as the cars go down the track, the potential energy is then changed to kinetic energy. Eventually the cars go up another hill and some of the kinetic energy is changed again to potential energy. This is the loop of energy...
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...Physics Lab 4 Part 1: Friction Parabola Track 3a. Kinetic energy is the highest when the skate board has reached its lowest point. 3b. Kinetic energy is the lowest when in the middle of the drop. 4a. Potential energy is the highest when the skate board has reached the highest point. 4b. Potential energy is lowest when in the middle of the drop. 5a. Total energy is the highest when potential energy is at its highest point. 6. The value of thermal energy is 0 only when potential energy is highest. David Del Rio Physics PH 2530 Lab 4 Energy 04/06/2015 Part 1: Loop Track 8. When a skateboarder moves, what happens to the kinetic and potential energy? Conservative (closed) or non-conservative (open) system? - Kinetic energy rises as the skateboarder moves downward. -potential energy rises as the skateboarder moves up. - Non-Conservative 9. Where is the skateboarder at on the ramp when he reaches the maximum point of potential energy? 4546.93 11. m = 76./kg The skateboarders mass = 76 kg 12a. calculated mass = 76 kg 12b. Actual mass 75 kg 12c. Comparison = .98% 13. When the coefficient is adjusted half way the kinetic energy decreases to 0 as to the potential energy decreases and finally stabilizes. - This is a closed system. Part 2: Friction Parabola Track 2a. kinetic energy is highest when the skaters’ board is at the lowest point 2b. in the middle of the drop the kinetic energy is highest. 3a. potential energy is the highest when the skaters’...
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...Different objects are made up of different molecules, and different molecules have their own properties with how they react to the elements and retain heat, how fast they heat, and how fast they cool. Heat is based on the total internal energy of the molecules of a body ( Tillery 2009). Larger object tend to have more internal energy than smaller objects, especially if the objects in question are the same substance, but if both object have the same temperature they are believed to have about the same molecular kinetic energy (Tillery 2009). The molecular energy is broken up into two different categories, external and internal energy. The difference between the two is that external energy refers the kinetic and potential energy of an every-day sized object, and internal refers the kinetic and potential energy of the molecules of an object. Take the tire on a car for example, it has external kinetic energy as it is rotating and that energy is transferred to the internal kinetic energy of the molecules between the tire and the surface of the road, which the consequence is both surface of the road and tire to be heated. The amount the road and tire are heated are directly related to how fast the tire is spinning and how much friction is being created between the two surfaces. This also serves as a good example for basic definition of heat, which can be described as the movement that occurs between two objects of different temperature when the objects are brought together. An example...
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