Precipitates and entropy

[jgalt42]

When solutions precipitate something, does this decrease the entropy of the system? If so, why?

 

[loveoforganic]

Entropy decreases because you're increasing the order of the system - you have essentially pure water and pure crystals as opposed to ions floating all through a solution. This is analagous to gas molecules all occupying one side of a chamber vs. the entire chamber.