Entropy

• Entropy (∆S) is the measure of the disorder of a system
• Entropy of a molecule is always zero
• Molecules in the solid phase have a lower entropy compared to the liquid and gas phase
• As mass increases so does entropy
• As the number of bonds in the molecules increases so does entropy
• If entropy is greater than zero the reaction is creating disorder and is spontaneous
• If entropy is less than zero the reaction is becoming more ordered
• Entropy can be positive or negative
• Positive entropy has more product molecules than reactant molecules
• Negative entropy has more reactant molecules than product molecules
• Increase in volume = Increased entropy (more particles)
• Increase in temperature = Increased entropy
• Entropy increases with phases (Solid<Liquid<<Gas)
• Entropy is calculate as follows:$S° rxn =$$∑ S° products - ∑ S° reactants$
• More motion = Greater entropy