3 ms·

> There's a large difference in energy and entropy between seawater and drinkable "fresh" water I agree with the entropy part, but isn't the energy practically

• at_a_remove 3y ago
  Really good question! The answer is: it's complicated. When you dissolve a "salt" (the whole class of them, rather than just NaCl), there is a lattice energy (you are tearing these crystals apart) and a hydration energy, which are a little give and take from an energy standpoint. Most salts dissolving are slightly exothermic. NaCl dissolving is very slightly endothermic. Seawater? Well, remember, there's a lot of dissolved solids in there, not just salts. So you have a summation of dissolving a whole menagerie of different things into your water. Last I heard, and it's been many years since I went near anything like that, yes, there's both an entropy and an energy cost, although I would personally dread trying to do calorimeter measurements to verify it experimentally.