Week 13

Thermodynamics

Concept Map of the Week

Note: image by Chudaeva, e. (2022).

Key terms

Review the following key terms (Glossary chapter 15):

entropy

a measurement of a system’s disorder and its inability to do work in a system

first law of thermodynamics

states that the change in internal energy of a system equals the net heat transfer into the system minus the net work done by the system

heat engine

a machine that uses heat transfer to do work

human metabolism

conversion of food into heat transfer, work, and stored fat

internal energy

the sum of the kinetic and potential energies of a system’s atoms and molecules

irreversible process

any process that depends on path direction

macrostate

an overall property of a system

microstate

each sequence within a larger macrostate

reversible process

a process in which both the heat engine system and the external environment theoretically can be returned to their original states

second law of thermodynamics

heat transfer flows from a hotter to a cooler object, never the reverse, and some heat energy in any process is lost to available work in a cyclical process

second law of thermodynamics stated in terms of entropy

the total entropy of a system either increases or remains constant; it never decreases

More terms can be found in the textbook Glossary.