Solute: The substance that dissolves in a solvent. In saltwater, NaCl (table salt) is the solute.
Solvent: The substance that dissolves the solute. In saltwater, water (H2O) is the solvent.
Dissolution of Salt in Water:
When you add salt to water, several things happen:
1. Polarity: Water molecules are polar, meaning they have a slightly positive end and a slightly negative end due to uneven sharing of electrons. This creates a strong attraction between water molecules.
2. Ionic Bonds: Salt (NaCl) is made of ionic bonds, where sodium (Na+) has a positive charge and chloride (Cl-) has a negative charge. These opposite charges attract each other strongly.
3. Attraction & Separation: When salt is added to water, the polar water molecules surround the salt ions. The positive ends of water molecules attract the negatively charged chloride ions (Cl-), while the negative ends of water molecules attract the positively charged sodium ions (Na+). This attraction weakens the ionic bonds between sodium and chloride.
4. Hydration: The water molecules form a hydration shell around each ion, effectively separating them and pulling them away from the salt crystal. This process continues until all the salt is dissolved.
5. Solution: The resulting mixture of dissolved salt ions and water molecules is called a solution.
In essence, when salt dissolves in water, the polar water molecules pull apart the ions in the salt crystal, creating a homogeneous mixture.
Important Note: While salt appears to disappear when dissolved in water, it doesn't actually vanish. The ions are still present in the solution, just evenly distributed and surrounded by water molecules. This is why saltwater tastes salty and can conduct electricity.
