Chapter 9 Thermodyamics Lecture 2 Flashcards
Chemical Reactions
involves breaking and forming chemical bonds, resulting in a change of chemical energy.
Chemical energy decreasing= Energy converted to thermal energy = Temp increases releases onto surroundings
Heat of Reaction
(q,rxn) Heat resulting from chemical reactions within the system
Exothermic reactions
System releases heat. CE -> TE
Temp increases. Heat is released to surroundings q;rx<0
Endothermic reaction
System absorbs heat: TE-> CE.
Temp decreases. Heat is absorbed into system. qrxn >0
Bomb calorimeter
Constant-volume calorimeter that is used to measure the heat of combustion. Formula Qcal=-Qrxn Temp of Calorimeter increases: Qxn= Ccal (Tf-Ti)
Pressure-Volume Work
Type of work done by the external pressure through volume change
Formula w= -P(Vf-Vi)
Different types of Work
System does work on the surrounding.
Volume = + w=P(Vf-Vi) = -
Surrounding does work on the system: Volume = - w= -P(Vf-Vi) = +