Calculating Concentration of Solutions

Definition of Concentration

• Concentration: Mass of a solute in a given volume of solution.
  • For Foundation Students: Learn this definition only.
  • For Higher Tier Students: Learn an additional definition in later lessons.

Solute and Solvent

• Solute: Chemical dissolved in a solvent.
• Common Solvent: Water.
• Concentration Unit: Grams per decimeter cubed (G/dm³).
  • Note: Decimeter cubed is equivalent to what was once called a liter.

Calculating Concentration

• Equation: Concentration = Mass (grams) / Volume (dm³).
  • Example 1: 200g of chemical dissolved in 1 dm³.
    • Concentration = 200 g/dm³.
  • Example 2: 150g of chemical dissolved in 0.5 dm³.
    • Concentration = 300 g/dm³.

Rearranging the Equation

• Calculate Mass: Concentration x Volume.
  • Example: Find mass for 0.4 dm³ solution with 600 g/dm³.
    • Mass = 240g.
• Calculate Volume: Mass / Concentration.
  • Example: Find volume for 200g with 800 g/dm³.
    • Volume = 0.25 dm³.

Effects on Concentration

• Increase Solute Mass, Constant Volume: Increases concentration.
• Increase Solution Volume, Constant Solute Mass: Decreases concentration.

Additional Resources

• More practice available in the revision workbook.

This summary should help you calculate the concentration of a solution in grams per decimeter cubed and understand how different variables affect concentration.