PPT-Enthalpy Calorimetry of Chemistry

Reaction Energies In our earlier discussions of calorimetry we used physical sources of heat hot metal slug It is also possible to use chemical sources of heat like hot packs and cold packs. Unit 1 – Chemical Changes and Structure. Controlling Rate. Factors Affecting Reaction Rate. Particle Size. The smaller the particle size, the greater the surface area, and the faster the reaction. Concentration. Quick Review of Concepts. We have been introduced to heat producing (. exothermic. ) reactions and heat using (. endothermic. ) reactions. Heat is a measure of the transfer of . energy. from a system to the surroundings and from the surroundings to a system. Fall, 2010 Indirect Calorimetry 1 Indirect Calorimetry Indirect Calorimetry CALORIMETRY The science that quantifies the heat release from metabolism is termed calorimetry . Figure 4.5 CALORIMETRY D Enthalpy. Enthalpy (H)is the total amount of energy contained within a substance. Included all forms of energy, kinetic, potential…. Very difficult to measure all forms of energy within a substance, therefore a change in enthalpies is measured whenever a change occurs.. calorimetry Enthalpy changes in reactions Calorimetry and heat measurement Hess’s Law Heats of formation Learning objectives • Describe the standard state for thermodynamic functions &# Heat Capacity. Specific Heat Capacity (c): . the quantity of thermal energy required to raise the temperature of 1 g of a substance by 1°C.. Units are in J/g∙°C. Heat Capacity. Specific . heat capacity values can be looked up in tables. Enthalpy . is a state function . (the pathway does not matter) with . the symbol . H. ..  . H . = E . P V. E . is the internal energy of the system, P is the pressure of the system, and V is the volume of the system.. Chapter. 4. Thermochemistry. Thermochemistry. is . the study of heat change in chemical reactions.. The . system. is . the specific part of the universe that is of interest in the study.. open. mass & energy. Why do chemical reactions happen?. Topic . 15: Energetics (. 8. . hours). 15.1 . Standard enthalpy changes of reaction. 15.1.1 . Define and apply the terms standard state, standard enthalpy change of formation (¬H ) f. Enthalpy . is a state function . (the pathway does not matter) with . the symbol . H. ..  . H . = E + . P V. E . is the internal energy of the system, P is the pressure of the system, and V is the volume of the system.. III. A 0.5269 g of octane is placed in a bomb calorimeter known to have a heat capacity of 11.3 kJ/. o. C.. The octane, a component of gasoline, is ignited in the presence of excess oxygen. The temperature is increased by 2.25. Thermochemistry. 1. st. Law of Thermodynamics- total energy of the universe is constant (p. 244). Definitions and State Functions. System. - a system is the part of the universe that is being studied. In Chemistry, this is often just a particular reaction (p. 243). SCOPE OF CONTENT OF MOE/GES CHEMISTRY SYLLABUS. THE . SCOPE OF THE SYLLABUS IS TO OFFER CHEMISTRY REQUIRED TO PROMOTE . AN UNDERSTANDING OF THE CHEMICAL PROCESSES TAKING PLACE ALL AROUND US.. SHS1. Change. First Law of Thermodynamics. Heat . (q. ). ,. work (. w. ) and internal energy (. E. ). Calculation of heat gained or lost by system. Calorimeter for measuring heat exchange (between system and surrounding;.