* No new substances are formed: The salt (NaCl) molecules simply separate and become surrounded by water molecules. The salt still exists, just in a different form.
* The change is reversible: You can evaporate the water and the salt will be left behind, retaining its original properties.
Here's a breakdown of what happens:
1. Attraction: Water molecules are polar, meaning they have a positive and negative end. Salt (NaCl) is an ionic compound, meaning it has positively charged sodium ions (Na+) and negatively charged chloride ions (Cl-). The polar water molecules attract the ions in the salt crystal.
2. Dissociation: The attraction between the water molecules and the ions is strong enough to overcome the forces holding the salt crystal together. The ions separate and become surrounded by water molecules, forming what's called a hydrated ion.
3. Solution: The hydrated ions are evenly distributed throughout the water, creating a salt solution.
Key point: Even though the salt appears to disappear, it's still present in the solution. You can prove this by evaporating the water and seeing the salt crystals reappear.
