Key Points:
* Solute: The substance that dissolves. Examples: sugar, salt, alcohol.
* Solvent: The substance that does the dissolving. Examples: water, oil, ethanol.
* Solution: The homogeneous mixture formed when the solute dissolves in the solvent.
How it works:
* Attraction: The molecules of the solute and solvent need to have some attraction for each other. This attraction can be based on various forces like:
* Hydrogen bonding: A strong attraction between polar molecules like water.
* Dipole-dipole interactions: Attraction between polar molecules.
* London dispersion forces: Weak attraction between nonpolar molecules.
* Breaking and forming bonds: The solute molecules break away from each other, and the solvent molecules break apart to make room for the solute molecules. New attractions form between the solute and solvent molecules.
* Even distribution: The solute molecules become dispersed throughout the solvent, creating a homogeneous mixture.
Factors affecting dissolution:
* Temperature: Higher temperature usually increases the rate of dissolution.
* Pressure: Increased pressure can increase the solubility of gases.
* Surface area: A larger surface area of the solute allows for faster dissolution.
* Stirring or agitation: Mixing helps distribute the solute faster.
Types of Solutions:
* Aqueous solution: Water is the solvent.
* Alcoholic solution: Ethanol is the solvent.
* Solid solution: One solid dissolves in another solid, like alloys (e.g., brass).
Important Note: Dissolution is not a chemical change. The molecules of the solute and solvent remain the same, just rearranged. You can often recover the original substances by evaporating the solvent.
