Overview
This lecture demonstrates the difference between dilute and concentrated solutions using copper(II) sulfate dissolved in water.
Demonstration: Dilute vs. Concentrated Solutions
- Two beakers each contain roughly 200 mL of water.
- A small amount of copper(II) sulfate is added to the right beaker, resulting in a faint blue color after stirring.
- A larger amount of copper(II) sulfate is added to the left beaker, creating a much more intense blue color.
- Some undissolved copper(II) sulfate remains in the left beaker until fully stirred, indicating the limit of solubility.
Concepts Explained
- A dilute solution has little solute dissolved per unit volume, resulting in lighter color intensity.
- A concentrated solution has a greater amount of solute dissolved per unit volume, yielding a stronger color.
- Color intensity in solutions often reflects the amount of solute present.
Key Terms & Definitions
- Solute — The substance dissolved in a solution (e.g., copper(II) sulfate).
- Solvent — The substance in which the solute dissolves (e.g., water).
- Dilute Solution — A solution with relatively few solute particles per unit volume.
- Concentrated Solution — A solution with many solute particles per unit volume.
- Solubility — The ability of a substance to dissolve in a solvent.
Action Items / Next Steps
- Review the definitions of dilute and concentrated solutions.
- Practice identifying dilute and concentrated solutions in lab or textbook examples.