15_Chapt5 - Thermochemistry Thermochemistry: Study of...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Mary J. Bojan Chem 110 Thermochemistry Energy kinetic potential First Law of Thermodynamics ! E = q + w Enthalpy ! H Thermochemical Equations Thermochemistry: Study of energy changes in chemical processes 2H 2 + O 2 " 2H 2 O + energy 1 ! H for chemical reactions Calorimetry, Heat Capacity Hess’s Law Heat of formation ! H f Standard State ! H ° f Foods and Fuels
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
First Law of Thermodynamics Law of conservation of energy Energy can be converted from one form to another… …but total energy remains constant. Mary J. Bojan 2 Chem 110
Background image of page 2
Mary J. Bojan Chem 110 Energy Kinetic Energy energy of motion Mechanical moving mass (1/2m v 2 ) Electrical moving charge Light photons Sound molecules moving uniformly Heat molecules moving randomly 3 Potential Energy stored energy Mechanical mass in a place where a force can act Chemical bonds Nuclear binding energy
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Mary J. Bojan Chem 110 Energy H # H + H # H + O=O " + 3 bonds 4 bonds 4 Electronic Energy The potential energy associated with the electrons in atoms and molecules Chemical energy the Potential Energy associated with bonding
Background image of page 4
Mary J. Bojan Chem 110 Changes in Energy w = work= action of force through a distance (often P ! V) work done to the system (+) q = heat (thermal energy) = energy transferred due to a difference in temperature. heat added to the system (+) 5 E = internal energy: total energy (E) associated with a system; the sum of all sources of kinetic & potential energy. the capacity to do work or transfer heat . ! E =E final - E initial = q + w
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Mary J. Bojan Chem 110 Changes in Energy 6 Energy lost by the SYSTEM is gained by the SURROUNDINGS. The system : what you are interested in a atom, molecule, or chemical reaction energy System ##" Surroundings ! E = " energy Surroundings ##" System ! E = +
Background image of page 6
Mary J. Bojan Chem 110 Energy changes Which one has more energy? Cool the water Heat the water 7
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Mary J. Bojan Chem 110 State Function a function whose value does not depend on the pathway used to get to the present state State Function: only depends on the current state (composition, T,P): does not depend on past history 8 ! E
Background image of page 8
Chem 110 State Functions State functions are written as uppercase letters (E, H, P, V, T, S…)
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 35

15_Chapt5 - Thermochemistry Thermochemistry: Study of...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online