@NOM4DCALwellnowurgentcare wrote:
I am trying to understand what kind of experiments have been preformed which have led us to the conclusion that ionic compounds like NaCl in something like water disassociate. From my understanding of the term disassociate this means to no longer be together or to be separate. So I wonder if this was the case how are saltwater purifiers working how is it that salt water purifiers do not sometimes pull more Na+ then Cl-. Maybe we are being taught using incorrect verbiage. Like not that they are completely dissociating but instead like we already teach ionic bonds are not particularly strong bonds and thus are easily persuaded to form other compounds which have stronger bonds. I am asking because I cannot seem to get a straight answer from any of my professors on the subject. A thought experiment I often ask them when they are adamant that they truly are dissociated is if we took 100mL’s of a solution of aqueous NaCl ( about 10% salt by volume) then take a syringe of 10mL’s of the solution and tested how much Na+ and Cl- was in the 10ml syringe there would still be 10% NaCl in the syringe so how can we say that the compound has dissociated? Is there some magic happening that causes them to be present in the same amount every time or is there still a bond between them?
Clarifying Ionic Dissociation (NaCl in Water)
When NaCl dissolves in water, it dissociates into Na⁺ and Cl⁻ ions. This means the solid NaCl breaks apart, and the ions are surrounded by water molecules, moving freely throughout the solution. While Na⁺ and Cl⁻ remain electrostatically attracted to each other, they are considered "dissociated" because they no longer form the solid NaCl structure.
Saltwater Purifiers and Ion Separation
Saltwater purifiers, like reverse osmosis or electrodialysis, don't favor one ion over the other because they remove both Na⁺ and Cl⁻ ions in roughly equal amounts. Even though the ions are separate in solution, their concentrations stay balanced across the system.
Key Point
Dissociation doesn't mean the ions are completely "separate" with no interaction; they are free to move independently but still maintain an overall uniform distribution in the solution. This is why if you take a sample, you'll find equal amounts of Na⁺ and Cl⁻, even though the ions are not bonded together in the way they are in solid NaCl.
Best regards,
Alice Richard
