Thermochemistry Essay

817 words - 4 pages

Thermochemistry is the application of thermodynamics to chemistry.Thermochemistry is used to predict the energy exchanges that occur in the following processes:1. chemical reactions2. phase changes such as boiling and melting3. the formation of solutionsThermochemistry is primarily concerned with the following state functions defined in thermodynamics:Internal energy (U)Enthalpy (H).Entropy (S)Gibbs free energy (G)Most identities in Thermochemistry arise from application of the first law of thermodynamics, the Law of Conservation of Energy, to these state function.In chemical reactions, bonds are broken and reformed, and heat may be given off or taken up in such processes. Since reactions are often carried out at constant pressure, the change in enthalpy is the appropriate measure of heat given off or absorbed.Laws of Thermochemistry1. The magnitude of H is directly proportional to the amount of reactant or product.-Thus H can be used as a ...view middle of the document...

Heat is not conserved, it can be either created or destroyed. In the metric system, heat is measured in units of calories, which are defined as the amount of heat required to raise the temperature of one gram of water from 14.5oC to 15.5oC.In the SI system, the unit of heat is the joule.Heat CapacityThe heat capacity of a substance is the amount of heat required to raise the temperature of a defined amount of pure substances by one degree (Celsius or Kelvin). The calorie was defined so that the heat capacity of water was equal to one.The specific heat of a substance is the number of calories needed to raise the temperature of one gram by 1oC. Because one degree on the Celsius scale is equal to one Kelvin, specific heats in the metric system can be reported in units of either cal/g-oC or cal/g-K. The units of specific heat in the SI system are J/g-K. Because there are 4.184 joules in a calorie, the specific heat of water is 4.184 J/g-K.The ease with which a substance gains or loses heat can also be described in terms of its molar heat capacity, which is the heat required to raise the temperature of one mole of the substance by either 1oC or 1 K. In the metric system, the units of molar heat capacities are therefore either cal/mol-oC or cal/mol-K. In the SI system the units of molar heat capacities are J/mol-K.Heat and The Kinetic Molecular TheoryThe system is the small portion of the universe in which we are interested, such as the water in a beaker or a gas trapped in a piston and cylinder, as shown in the figures below. The surroundings are everything else in other words, the rest of the universe.The system and its surroundings are separated by a boundary. Heat is transferred across the boundary between a system and its surroundings.One of the fundamental principles of the kinetic theory is the assumption that the average kinetic energy of a collection of gas particles depends on the temperature of the gas and nothing else. A gas becomes warmer if and only if the average kinetic energy of the gas particles increases. Heat, when it raises the temperature of a system, produces an increase in the speed with which the particles of the system move, as shown in the figure below.

Other Essays On Thermochemistry

Master and slave. an analysis

495 words - 2 pages Each of the characters in The Tempest finds themselves in bondage. However, by the end of the story, the same characters are set free from whatever enslaves them. A few characters one can see enslaved are Prospero, Miranda, Ariel, and Caliban.Prospero is in bondage to his magic. Since his exile by his brother from his dukedom in Milan, he has had but a few books to help pass the twelve long years. During this time, he becomes very proficient in

Methods Of Therapy Essay

2480 words - 10 pages METHODS OF THERAPY Therapy, from a psychologist's viewpoint, has many different meanings. It can be physical or psychological, or even both. In this paper, several different aspects of therapy will be discussed. First the word therapy will be defined more clearly, and then psychotherapy and how it differs from other interactions yet is also similar. Next therapy will be examined from the Psychodynamic, Cognitive and Humanistic-Existential points

Phineas And Gene A Comparitive

1538 words - 7 pages Phineas and Gene: A Comparative Study Throughout the story, Phineas and Gene, the two main characters, showed a number of contrasting traits. Phineas was a confident, non competitive, naive, irresponsible, and unintelligent person throughout the story, whereas Gene, Phineas' roommate, was insecure, competitive, mature, responsible, and intelligent throughout the story.Phineas had a confident nature in everything he did. As Phineas and Gene first

Mafia

2008 words - 9 pages Mafia. What does this word mean? The actual members of the Mafia aren't even sure where the word first originated or what it really means. One of the theories as to where the word came from is from Sicily, where people would yell " Morte alla Francia, Italia anela!" (Death to France, Italy groans!), therefore forming the acronym MAFIA. Others claim the word derived from the battle cry of rebels who slaughtered thousands of Frenchmen after a

Baseball Strike

1354 words - 6 pages GAME OVER! "I don't like it. People won't be able to come to these games anymore, and I don't like that". A sad nine - year - old fan voices his concerns on the 1994 major League Baseball strike. The '94 baseball season has come to an abrupt end. Players have ceased play because they feel they are being treated unfairly with the owner's plan to impose a salary cap. Owners are finding it difficult to come to terms with their own disagreements

Worst experience

299 words - 2 pages I wanted to lie down and cry. When I got home from the student/teacher/parent conference in fifth grade my mind was in shambles. After I had done everything possible to pass math, my fifth grade teacher was actually telling my Parents about my alleged poor effort. Poor effort? Didn't I do every homework assignment? Didn't I study every night and miss my favorite television show "Full house"? From an early age, I had been taught that grades are

Multinational Companies

2058 words - 9 pages Multinational Companies: Out for Profit Without Regard for Life                  What a company usually wants for its business is for it to be an successful establishment and to make an abundance of profit. Some businesses do not pose any concern on what they have to do to make this profit as long as it done. Multinational companies are firms with their home base in one country and operations in many other nations. (Molyeux, 133

Middle Adulthood 2

675 words - 3 pages The Dictionary of Social Work roughly defines middle adulthood as the period between forty-five and sixty-four years of age. There are four main tasks in this stage. They include meeting intimacy and family needs, satisfying achievement needs, taking care of elderly parents, and coping with end of life issues. Erikson identifies the need for achievement during midlife, which fits into his stage of generativity vs. stagnation. Success in adulthood

Political socialization

461 words - 2 pages Political Socialization There are many ways that our ideas are shaped and influenced as we grow up. This process by which we develop certain ways of thinking is called political socialization. There are three main influences which change and shape us being, the family, the mass media, and formal education.The family definitely has the greatest impact on us as we grow. This is primarily because ever since the beginning of childhood we are exposed

Procrastination and regrets

533 words - 3 pages Procrastination and Regrets It's Thursday afternoon and Jack has nothing to do except his homework. However, Jack doesn't feel like doing his homework, so he thinks to himself "I'll do my homework tomorrow night and go to a house party tonight." Ah yes, like many other young adults, Jack has resorted to procrastination. The procrastination bug, like young adults has also become abundant in parents.One thing that many young adults procrastinate

Frank o haras the day lady die

398 words - 2 pages In his poem, "The Day Lady Died", Frank O'Hara refrains from using all the conventional patterns of elegiac poetry. Instead of the common reflection of grief, utilizing tragic laments and a recount of greatness now gone, O'Hara's seemingly ordinary poem very subtly evokes a sense of loss. At first, O'Hara's poem appears to be the account of a very typical day. His classic "I do this and I do that" style, accompanied by the simplistic description

Similar Papers

Thermochemistry General Chemistry Unh General Chemistry Unh Assigment

3683 words - 15 pages CHEM 403 Fall 2018 1 Thermochemistry Goals and Challenges: The following experiments concern heat: heat flow, heat production and the relationship with bond breaking and bond making. In Part I, you will study heats of dissolution; in Part II, you will model the relationship between heat and bond breaking and making and will then determine the heat of combustion of methanol via calorimetry. Bring to lab:  Lab notebook  Safety eyewear, lab

Thermodynamics And Thermometers Nagpayong High School Essay

510 words - 3 pages General Chemistry II Thermochemistry Name:_________________________________________ Section: _____________ Score:______________ Date: _____________ (Wag mo ako lokohin! Wala ka nun. HAHAHAHAH) Problem Set #1 1. A piece of an unknown metal weighs 550. g and requires 9.315 kJ of energy to increase its temperature from 22.0 °C to 65.2 °C. What is the specific heat capacity of the metal? 2

Persuasive Essay Gay And Lesbi

623 words - 3 pages Persuasive Essay - Gay and Lesbian Rights "If anyone says, 'I love God,' yet hates his brother, he is a liar. For anyone who does not love his brother, whom he has seen cannot love God, whom he has not seen," John 4:20. So, why do heterosexual people hate homosexuals? They are ordinary people with a different lifestyle who would simply like to be treated with respect. Many organized religions believe that a 'gay' lifestyle is wrong. But, if

Mark Mcgwire Vs Sammy Sosa Essay

1206 words - 5 pages Although a lot of people play baseball two names that come to mind are Mark McGwire and Sammy Sosa. McGwire and Sosa are very good hitters but are also so very different hitters. McGwire and Sosa are very great athletes who share apart of baseball history. McGwire and Sosa are good players but off the field they are very charitable individuals. McGwire and Sosa have many similarities and differences. IT is hard to compare Mark McGwire and