Topic 12: Entropy & Energetics

Entropy

is a measure of disorder of a system in terms of the random dispersal of molecules and of energy quanta between molecules

Entropy increases with …

• temperature

• number of moles

• solid, liquid, gas

exothermic reactions

• energy is given to the surroundings

• arrangement ways increases

• ΔS surroundings +

endothermic reactions

• energy is taken from surroundings

• arrangement ways decreases

• ΔS surroundings -

ΔH sol is highly exothermic

very soluble

ΔH sol is small endothermic

more + more soluble

ΔH sol is highly endothermic

insoluble

higher lattice energy

lower solubility

higher hydration energy

higher solubility