Aperçu des sections

  • Généralités

    Tout replier Tout déplier

  • COURSETITLE: CHEMICALTHERMODYNAMICS

     


  • DEFINITIONS ET CONCEPTION DE BASES

          


  • FIRST LAW OF THERMODYNAMICS:CONSERVATIONOF ENERGY


  • 3.0 First law of thermodynamics



  • 3.0 Thermochemicalequations

    Thermochemistry is concerned with energy and heat accompanying a chemical reaction, physicaltransformations or both processes. During such changes, energy is either absorbed or given out.For example, the chemical reaction between hydrogen and oxygen gases during the formation ofwaterisexothermic.However,theheatofvapourizationofwaterisendothermic.Thermochemistry study these energy changes, particularly on the system‘s energy exchange withits surroundings. The heat that flows across the boundaries of a system ( to the surrounding)undergoing a change is a fundamental property that characterizes the process. Thermochemistryoffers a quantitative method of measuring the heat and enthalpy changes in a system duringreactionorphasetransition.

    Thermochemistryhassomebasicadvantages.Firstitcanbeused,alongwithotherthermodynamic parameters to predict the spontaneity or feasibility of a given reaction. Based onthe exchange*of heatbetween the system andthe surrounding,chemical reactions canbeclassifiedintotwo,namely,exothermicandendothermicreactions.Endothermicreactionsabsorbheatfromthesurroundingwhileexothermicreactionsreleaseheattothesurrounding.