CHE2B-LEC 01 CHAP 07 - Chapter 7 Why study thermochemistry...

TOUPADAKIS Chapter 7 Lecture 1
Chapter 7
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What determines which reactions can occur?
•
Why places near ocean or large lakes have mild climate
with no extreme temperatures?
•
How is sun’s energy stored in carbohydrates and how is it
released in a living tissue?
Why study thermochemistry?
In order to answer questions like:

TOUPADAKIS Chapter 7 Lecture 1
Lecture 1
•
Basic definitions of work and energy.
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Energy possessed by a system (kinetic and potential).
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Energy in transfer between a system and its surroundings
(heat and work).
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Three types of systems (open, closed, isolated).
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Thermodynamics versus thermochemistry.
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Exothermic versus endothermic reactions.
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Heat capacity and its measurement.
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Sign conventions.
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Types of work (pressure-volume work).

TOUPADAKIS Chapter 7 Lecture 1
Work and Energy
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Work
(physics)
Motion against an opposing force.
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Energy
The capacity of a system to do work.
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Work
(a simple definition from thermodynamics )
The energy used to cause an object to move against an opposing force.
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Work
(a general definition from thermodynamics)
Work is energy flowing across a system’s boundary for any reason,
except of a temperature difference between the system and its
surroundings.

TOUPADAKIS Chapter 7 Lecture 1
Work is energy in transfer. Therefore we cannot say
for example that a system contains 100 J of work.