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Entropy. http://www.youtube.com/watch?v=uQSoaiubuA0. Entropy. Entropy is a measure of disorder, and is given the symbol S . The units of S are: J K –1 mol –1. ordered. disordered. regular arrangement of particles. random arrangement of particles. low entropy. high entropy.
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Entropy http://www.youtube.com/watch?v=uQSoaiubuA0
Entropy Entropy is a measure of disorder, and is given the symbol S. The units of S are: JK–1mol–1. • ordered • disordered • regular arrangement of particles • random arrangement of particles • low entropy • high entropy
Calculating entropy changes Standard entropy changes for any chemical reaction or physical change can be calculated using the following simple expression: DS = SSөproducts – SSөreactants Remember the following points: • the units of entropy, S, are JK–1mol–1 • entropies of elements are not zero like DHf values, so they should be included in calculations.