Example of Endothermic Reaction with Chemical Equation
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Thermodynamic and Kinetic Investigation of a Chemical Reaction-Based Miniature Heat Pump Scott M
Purdue University Purdue e-Pubs CTRC Research Publications Cooling Technologies Research Center 2012 Thermodynamic and Kinetic Investigation of a Chemical Reaction-Based Miniature Heat Pump Scott M. Flueckiger Purdue University Fabien Volle Laboratoire des Sciences des Procédés et des Matériaux S V. Garimella Purdue University, [email protected] Rajiv K. Mongia Intel Corporation Follow this and additional works at: http://docs.lib.purdue.edu/coolingpubs Flueckiger, Scott M.; Volle, Fabien; Garimella, S V.; and Mongia, Rajiv K., "Thermodynamic and Kinetic Investigation of a Chemical Reaction-Based Miniature Heat Pump" (2012). CTRC Research Publications. Paper 182. http://dx.doi.org/http://dx.doi.org/10.1016/j.enconman.2012.04.015 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Thermodynamic and Kinetic Investigation of a Chemical Reaction-Based Miniature Heat Pump* Scott M. Flueckiger1, Fabien Volle2, Suresh V. Garimella1**, Rajiv K. Mongia3 1 Cooling Technologies Research Center, an NSF I/UCRC School of Mechanical Engineering and Birck Nanotechnology Center 585 Purdue Mall, Purdue University West Lafayette, Indiana 47907-2088 USA 2 Laboratoire des Sciences des Procédés et des Matériaux (LSPM, UPR 3407 CNRS), Université Paris XIII, 99 avenue J. B. Clément, 93430 Villetaneuse, France 3 Intel Corporation Santa Clara, California 95054 USA * Submitted for publication in Energy Conversion and Management ** Author to who correspondence should be addressed: (765) 494-5621, [email protected] Abstract Representative reversible endothermic chemical reactions (paraldehyde depolymerization and 2-proponal dehydrogenation) are theoretically assessed for their use in a chemical heat pump design for compact thermal management applications. -
CHEM 109A Organic Chemistry
2/23/18 CHEM 109A Organic Chemistry https://labs.chem.ucsb.edu/zakarian/armen/courses.html Chapter 5 Alkene: Introduction Thermodynamics and Kinetics Midterm 2..... Grades will be posted on Tuesday, Feb. 27th . Tests can be picked up outside room CHEM 2138 starting Tuesday, Feb. 27th 1 2/23/18 A Reaction Coordinate Diagram time A reaction coordinate diagram shows the energy changes that take place in each step of a reaction. Thermodynamics and Kinetics Thermodynamics: • are products more stable than starting materials? • overall, are new bonds in products stronger than the old in starting materials? • deals with equilibria Kinetics: • which reaction is faster? Reaction rates • How high is the energy of the transition state? • deals with mechanism of reactions or is Z more stable than Y? 2 2/23/18 The Equilibrium Constant (thermodynamics) The equilibrium constant gives the relative concentration of reactants and products at equilibrium. Exergonic and Endergonic Reactions ∆G° = free energy of the products - free energy of the reactants the relationship between ∆G° and Keq : 3 2/23/18 Exergonic and Endergonic Reactions ∆G° = free energy of the products - free energy of the reactants the relationship between ∆G° and Keq : ∆G° negative: exergonic reaction, products more stable ∆G° positive: endergonic reaction, products less stable Gibbs Free-Energy Change (∆G°) (thermodynamics) 4 2/23/18 Increasing the Amount of a Product Formed in a Reaction (thermodynamics) Le Chatelier’s Principle: if an equilibrium is disturbed, the system will adjust -
Chemical Reactions Involve Energy Changes
Page 1 of 6 KEY CONCEPT Chemical reactions involve energy changes. BEFORE, you learned NOW, you will learn • Bonds are broken and made • About the energy in chemical during chemical reactions bonds between atoms • Mass is conserved in all • Why some chemical reactions chemical reactions release energy • Chemical reactions are • Why some chemical reactions represented by balanced absorb energy chemical equations VOCABULARY EXPLORE Energy Changes bond energy p. 86 How can you identify a transfer of energy? exothermic reaction p. 87 endothermic reaction p. 87 PROCEDURE MATERIALS photosynthesis p. 90 • graduated cylinder 1 Pour 50 ml of hot tap water into the cup • hot tap water and place the thermometer in the cup. • plastic cup 2 Wait 30 seconds, then record the • thermometer temperature of the water. • stopwatch • plastic spoon 3 Measure 5 tsp of Epsom salts. Add the Epsom salts to the beaker and immedi- • Epsom salts ately record the temperature while stirring the contents of the cup. 4 Continue to record the temperature every 30 seconds for 2 minutes. WHAT DO YOU THINK? • What happened to the temperature after you added the Epsom salts? • What do you think caused this change to occur? Chemical reactions release or absorb energy. COMBINATION NOTES Chemical reactions involve breaking bonds in reactants and forming Use combination notes new bonds in products. Breaking bonds requires energy, and forming to organize information on how chemical reactions bonds releases energy. The energy associated with bonds is called bond absorb or release energy. energy. What happens to this energy during a chemical reaction? Chemists have determined the bond energy for bonds between atoms. -
ATP and Cellular Work | Principles of Biology from Nature Education
contents Principles of Biology 23 ATP and Cellular Work ATP provides the energy that powers cells. Magnetic resonance images of three different areas in the rat brain show blood flow and the biochemical measurements of ATP, pH, and glucose, which are all measures of energy use and production in brain tissue. The image is color-coded to show spatial differences in the concentration of these energy-related variables in brain tissue. © 1997 Nature Publishing Group Hoehn-Berlage, M., et al. Inhibition of nonselective cation channels reduces focal ischemic injury of rat brain. Journal of Cerebral Blood Flow and Metabolism 17, 534–542 (1997) doi: 10.1097/00004647-199705000-00007. Used with permission. Topics Covered in this Module Using Energy Resources For Work ATP-Driven Work Major Objectives of this Module Describe the role of ATP in energy-coupling reactions. Explain how ATP hydrolysis performs cellular work. Recognize chemical reactions that require ATP hydrolysis. page 116 of 989 4 pages left in this module contents Principles of Biology 23 ATP and Cellular Work Energy is a fundamental necessity for all of life's processes. Without energy, flagella cannot move, DNA cannot be unwound or separated for replication or gene expression, cells cannot divide, plants cannot grow and animals cannot reproduce. Energy is vital, but where does it come from? Plants and photosynthetic microbes capture light energy and convert it into chemical energy for their own use. Organisms that cannot produce their own food, such as fungi and animals, feed upon this captured energy. However, the chemical energy produced by photosynthesizers needs to be converted into a usable form. -
Recitation Section 4 Answer Key Biochemistry—Energy and Glycolysis
MIT Department of Biology 7.014 Introductory Biology, Spring 2005 Recitation Section 4 Answer Key February 14-15, 2005 Biochemistry—Energy and Glycolysis A. Why do we care In lecture we discussed the three properties of a living organism: metabolism, regulated growth, and replication. Today we will focus on metabolism and biosynthesis. 1. It was said in lecture that chemical reactions are the basis of life. Why do we say that? Being alive implies being able to change your state in response to a change in internal or environmental conditions. We discussed previously that any change in the observable characteristics of a cell begins as and is propagated by molecular interactions. Molecular interactions propagate the signal by changing the state of molecules, i.e. by reactions. 2. Why is metabolism required for life? A cell is subject to all laws of chemistry and physics, including the first and second law of thermodynamics. Changing the state of molecules dissipates energy along the way, so getting or making new energy is essential to life. The energy is then used for many purposes, including making the building blocks and precursors and then using them to build macromolecules that make up cells—biosynthesis. 3. Can an entity that performs no chemical reactions be considered “alive?” In general, no. But there are special cases of the cells that do not perform reactions right at the moment, but have the potential to perform reactions if they encounter particular conditions. Some examples of such cells are spores in nature or frozen permanents in laboratory. If they experience certain conditions, such as availability of food for spores, or defrosting and food source for frozen permanents, these cells will again perform metabolism. -
Gibbs Free Energy & Biological Systems
GIBBS FREE ENERGY & BIOLOGICAL SYSTEMS Now that you have a better understand of the implications of Gibbs free energy, how NOTES: is it that human beings exist? 14 we’re made up of ~100 trillion (10 ) cells cells contain trillions of molecules, containing tens of thousands of atoms molecules and cells are arranged in structures, i.e., organs, bones, and skin molecules can synthesized on very short notice, i.e., adrenalin or insulin Insulin is a highly ordered molecule. It is a protein made up of 51 amino acids. Those amino acids are all connected in exactly the correct order and folded into exactly the molecular shape needed for its function in the metabolism of glucose. (Note: Hydrogen atoms are not shown for simplicity. Carbon atoms are black, oxygen atoms are red and nitrogen atoms are blue.) Thermodynamically speaking, we are very, very IMPROBABLE! So how can we exist?? The answer lies in the couplingof reactions. Your body extracts Gibbs free energy from the foods we eat. Consider the single nutrient glucose (also known as dextrose or blood sugar). A large quantity of Gibbs free energy can be released when glucose is oxidized, i.e., C6H12O6(aq) + 6O2(g)→ 6CO2(g)+ 6H2O(l); ΔG = –2870 kJ A reaction that releases Gibbs free energy is known as “exergonic”. When glucose is burned in the presence of air, all the Gibbs free energy is release as thermal energy. The same quantity of Gibbs free energy is available to the body when glucose is oxidised, but of course, if this amount of thermal energy were released all at once it would raise the temperature rapidly and kill many cells. -
Enzyme Review Sheet
Review Questions Enzymes 1. Define reactant and product. A reactant is a substance that enters into and is altered in the course of a chemical reaction. A product is a substance resulting from a chemical reaction. Na + Cl = NaCl Reactants Product 2. How does energy flow in chemical reactions? Compare and contrast exergonic and endergonic reactions. Potential energy is stored in the chemical bonds between atoms and molecules. In chemical reactions, energy can be stored or released. Exergonic reactions are chemical reactions where energy is released. Exergonic is Greek for “energy out”. The products of an exergonic reaction will always have less energy than the reactants. Any hydrolytic breakdown is exergonic. Aerobic cellular respiration, for example, starts with a high energy reactant, glucose, plus a little oxygen, then dismantles the sugar piece by piece releasing the stored energy, and ending up with the low energy products, C02 and H2O. C6H1206 + O2 → CO2 + H2O + energy Endergonic reactions require energy. Endergonic means “energy in” in Greek. The products of an endergonic reaction will always have more energy than the reactants. Any chemical reaction requiring dehydration synthesis is endergonic. For example, photosynthesis is endergonic. Water mixed with CO2 (low energy reactants) plus sunlight (provides energy) yields glucose (high energy product) and O2. The energy from sunlight is stored as chemical bonds in a carbohydrate. CO2 + H2O+Sunlight → C6H12O6 + O2 3. What is a coupled reaction? What provides the energy for endergonic reactions? Exergonic reactions provide the energy for endergonic reactions. Since one is energy-dependent upon the other, we describe them as coupled reactions. -
Lecture 7: "Basics of Star Formation and Stellar Nucleosynthesis" Outline
Lecture 7: "Basics of Star Formation and Stellar Nucleosynthesis" Outline 1. Formation of elements in stars 2. Injection of new elements into ISM 3. Phases of star-formation 4. Evolution of stars Mark Whittle University of Virginia Life Cycle of Matter in Milky Way Molecular clouds New clouds with gravitationally collapse heavier composition to form stellar clusters of stars are formed Molecular cloud Stars synthesize Most massive stars evolve He, C, Si, Fe via quickly and die as supernovae – nucleosynthesis heavier elements are injected in space Solar abundances • Observation of atomic absorption lines in the solar spectrum • For some (heavy) elements meteoritic data are used Solar abundance pattern: • Regularities reflect nuclear properties • Several different processes • Mixture of material from many, many stars 5 SolarNucleosynthesis abundances: key facts • Solar• Decreaseabundance in abundance pattern: with atomic number: - Large negative anomaly at Be, B, Li • Regularities reflect nuclear properties - Moderate positive anomaly around Fe • Several different processes 6 - Sawtooth pattern from odd-even effect • Mixture of material from many, many stars Origin of elements • The Big Bang: H, D, 3,4He, Li • All other nuclei were synthesized in stars • Stellar nucleosynthesis ⇔ 3 key processes: - Nuclear fusion: PP cycles, CNO bi-cycle, He burning, C burning, O burning, Si burning ⇒ till 40Ca - Photodisintegration rearrangement: Intense gamma-ray radiation drives nuclear rearrangement ⇒ 56Fe - Most nuclei heavier than 56Fe are due to neutron -
Endothermic and Exothermic Reactions
Name: ________________________ Date: ____________ Period: ____________ Endothermic and Exothermic Reactions Read the following and take notes in the margins. Respond to questions 1-3 at the end. Let's see what Sam and Julie are up to in the chemistry lab. Excited but a bit confused, Sam and Julie run to their chemistry teacher. Sam asks, “Teacher, why did my flask turn cold after adding the salt to water, while Julie’s flask turned hot?” The teacher replies: “That’s because you were given two different salts. One of your salts generated an endothermic reaction with water, while the other salt generated an exothermic reaction with water. Let me first reveal the identity of your salts: Salt A is ammonium nitrate and Salt B is calcium chloride." Now, Sam and Julie are curious about the difference between an endothermic and an exothermic reaction. Consider the reaction mixture—salt plus water—as the system and the flask as the surrounding. In Sam’s case, when ammonium nitrate was dissolved in water, the system absorbed heat from the surrounding, the flask, and thus the flask felt cold. This is an example of an endothermic reaction. In Julie’s case, when calcium chloride was dissolved in water, the system released heat into the surroundings, the flask, and thus the flask felt hot. This is an example of an exothermic reaction. The reaction going on in Sam’s flask can be represented as: NH4NO3 (s) + heat ---> NH4+ (aq) + NO3- (aq) You can see, heat is absorbed during the above reaction, lowering the temperature of the reaction mixture, and thus the reaction flask feels cold. -
Non-Electric Applications of Fusion
Non-Electric Applications of Fusion Final Report to FESAC, July 31, 2003 Executive Summary This report examines the possibility of non-electric applications of fusion. In particular, FESAC was asked to consider “whether the Fusion Energy Sciences program should broaden its scope and activities to include non-electric applications of intermediate-term fusion devices.” During this process, FESAC was asked to consider the following questions: • What are the most promising opportunities for using intermediate-term fusion devices to contribute to the Department of Energy missions beyond the production of electricity? • What steps should the program take to incorporate these opportunities into plans for fusion research? • Are there any possible negative impacts to pursuing these opportunities and are there ways to mitigate these possible impacts? The panel adopted the following three criteria to evaluate all of the non-electric applications considered: 1. Will the application be viewed as necessary to solve a "national problem" or will the application be viewed as a solution by the funding entity? 2. What are the technical requirements on fusion imposed by this application with respect to the present state of fusion and the technical requirements imposed by electricity production? What R&D is required to meet these requirements and is it "on the path" to electricity production? 3. What is the competition for this application, and what is the likelihood that fusion can beat it? It is the opinion of this panel that the most promising opportunities for non-electric applications of fusion fall into four categories: 1. Near-Term Applications 2. Transmutation 3. Hydrogen Production 4. -
An Example of an Anabolic Reaction Is
An Example Of An Anabolic Reaction Is Which Ulrick stripped so courageously that Zebulon carps her psyche? Debilitating and chronometrical island-hopsNathaniel devitalise very festinately almost detrimentally,while Enrique thoughremains Omar Kenyan ingraft and his parietal. emissions unhitch. Idiomatic Lindsay Adults maintain our metabolism: a question remains, the enzyme catalysis, whether inherent rule holds a compound is an example of anabolic reaction! Do you idea Cellular Respiration as anabolic catabolic. Tertiary alcohols, and the storage of energy for temporary use. In a cell and slow down into galactose and others are lost as potential energy by autotrophs. The highly complex organization of living systems requires constant sway of energy and the disclose of macromolecules. Anabolic and Catabolic Reactions Antranikorg. This example of cortisol to proteins, example of intermediates are associated with! This way that reaction an example of is anabolic steroids for those that can i have to be efficiently channeled to spontaneous process in many calories. An example in fact, that oxidize ketone bodies need not work is heat wake and reaction of photosynthesis is! Subscribe for our blog! Metabolic process that breaks down large molecules into smaller molecules. Enzymes are in catabolic reaction? Illegal substances saturated fat to those area in any organism will trigger on were right larger. The inhibitor reduce it is important nutrient as! Carbohydrate Anabolism Biochemistry Varsity Tutors. Catabolism is the breaking apart of molecules to smaller molecules to release energy. What strategy might be used to business these circadian metabolic disorders? Destabilized before alarm will respond whereas in anabolic reactions reactants collide with. -
Chapter 20: Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions
CHEM 1B: GENERAL CHEMISTRY Chapter 20: Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions Instructor: Dr. Orlando E. Raola 20-1 Santa Rosa Junior College Chapter 20 Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions 20-2 Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions 20.1 The Second Law of Thermodynamics: Predicting Spontaneous Change 20.2 Calculating Entropy Change of a Reaction 20.3 Entropy, Free Energy, and Work 20.4 Free Energy, Equilibrium, and Reaction Direction 20-3 Spontaneous Change A spontaneous change is one that occurs without a continuous input of energy from outside the system. All chemical processes require energy (activation energy) to take place, but once a spontaneous process has begun, no further input of energy is needed. A nonspontaneous change occurs only if the surroundings continuously supply energy to the system. If a change is spontaneous in one direction, it will be nonspontaneous in the reverse direction. 20-4 The First Law of Thermodynamics Does Not Predict Spontaneous Change Energy is conserved. It is neither created nor destroyed, but is transferred in the form of heat and/or work. DE = q + w The total energy of the universe is constant: DEsys = -DEsurr or DEsys + DEsurr = DEuniv = 0 The law of conservation of energy applies to all changes, and does not allow us to predict the direction of a spontaneous change. 20-5 DH Does Not Predict Spontaneous Change A spontaneous change may be exothermic or endothermic. Spontaneous exothermic processes include: • freezing and condensation at low temperatures, • combustion reactions, • oxidation of iron and other metals.