1. Polarity and Attraction: Water molecules are polar, meaning they have a slightly positive end (hydrogen) and a slightly negative end (oxygen). Salt crystals, on the other hand, are made of ions: positively charged sodium ions (Na+) and negatively charged chloride ions (Cl-).
2. Hydration: Water molecules are attracted to the ions in the salt crystal. The positive ends of water molecules surround the chloride ions, and the negative ends surround the sodium ions. This attraction is called hydration.
3. Breaking Apart: The strong attraction between the water molecules and the ions overcomes the ionic bonds holding the salt crystal together. The salt crystal begins to break apart, releasing individual ions into the water.
4. Solution: The dissolved ions are now surrounded by water molecules, preventing them from recombining into a crystal. The water now contains dissolved salt, forming a salt solution.
What happens to the salt crystal itself?
The salt crystal will eventually disappear as it completely dissolves into the water. The size of the crystal will gradually decrease as more and more ions are released.
Factors affecting dissolution:
* Temperature: Warmer water dissolves salt faster because the increased kinetic energy of the molecules helps break apart the crystal lattice more easily.
* Stirring: Stirring the water helps bring fresh water molecules into contact with the salt crystal, accelerating the process.
* Concentration: If the water already contains a lot of dissolved salt, it will be harder for more salt to dissolve (saturation).
Important note: This process is reversible. If you evaporate the water, the salt ions will recombine and form salt crystals again.
