Jump to ContentJump to Main Navigation
Chemistry in Quantitative LanguageFundamentals of General Chemistry Calculations$
Users without a subscription are not able to see the full content.

Christopher O. Oriakhi

Print publication date: 2009

Print ISBN-13: 9780195367997

Published to Oxford Scholarship Online: November 2020

DOI: 10.1093/oso/9780195367997.001.0001

Show Summary Details
Page of

PRINTED FROM OXFORD SCHOLARSHIP ONLINE (oxford.universitypressscholarship.com). (c) Copyright Oxford University Press, 2021. All Rights Reserved. An individual user may print out a PDF of a single chapter of a monograph in OSO for personal use. date: 18 October 2021

Chemical Thermodynamics

Chemical Thermodynamics

Chapter:
21 (p.355) Chemical Thermodynamics
Source:
Chemistry in Quantitative Language
Author(s):

Christopher O. Oriakhi

Publisher:
Oxford University Press
DOI:10.1093/oso/9780195367997.003.0025

Chemical thermodynamics is the study of the energy changes and transfers associated with chemical and physical transformations. Energy is the ability to do work or to transfer heat. A spontaneous process is one that can occur on its own without any external influence. A spontaneous process always moves a system in the direction of equilibrium. When a process or reaction cannot occur under the prescribed conditions, it is nonspontaneous. The reverse of a spontaneous process or reaction is always nonspontaneous. Heat (q) is the energy transferred between a system and its surroundings due to a temperature difference. Work (w) is the energy change when a force (F) moves an object through a distance (d). Thus. . . W = F ×d. . . . A system is a specified part of the universe (e.g., a sample or a reaction mixture we are studying). Everything outside the system is referred to as the surroundings. The universe is the system plus the surroundings. A state function is a thermodynamic quantity that defines the present state or condition of the system. Changes in state function quantities are independent of the path (or process) used to arrive at the final state from the initial state. Examples of state functions include enthalpy change (ΔH), entropy change, (ΔS) and free energy change, (ΔG). The internal energy of a system is the sum of the kinetic and potential energies of the particles making up the system. While it is not possible to determine the absolute internal energy of a system, we can easily measure changes in internal energy (which correspond to energy given off or absorbed by the system). The change in internal energy, . . . ΔE, is: ΔE = Efinal –Einitial. . . . The first law of thermodynamics, also called the law of conservation of energy, states that the total amount of energy in the universe is constant, that is, energy can neither be created nor destroyed. It can only be converted from one form into another. In mathematical terms, the law states that the change in internal energy of a system, ΔE, equals q+w. That is,. . . ΔE = q+w. . . In other words, the change in E is equal to the heat absorbed (or emitted) by the system, plus work done on (or by) the system.

Keywords:   energy, system

Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.

Please, subscribe or login to access full text content.

If you think you should have access to this title, please contact your librarian.

To troubleshoot, please check our FAQs , and if you can't find the answer there, please contact us .