1. Different Ways of Expressing Concentration Grade 10 ST

2. Concentration A solution is composed of a solute dissolved in a solvent Solute: substance being dissolved Solvent: substance doing the dissolving Concentration: the amount of solute in a given quantity of solvent

3. Ways of Expressing Concentration In g/L 6 g/L means “6g of solute dissolved in 1 L of solution” To find the concentration, we can use the formula Formula: C= m V C= concentration (g/L) m= mass of solute (g) V= Volume of solvent (L)

4. Ways of Expressing Concentration As % (m/V) 12 % (m/V) means “ 12 g of solute dissolved in 100 mL of solution” To solve problems, set – up a ratio and cross multiply

5. % (m/V) Example 40 g of Kool –Aid are dissolved in 1.2 L of solution. What is the concentration of this solution expressed as a % (m/V)

6. % (m/V) Example A 600 mL volumetric flask is filled with a solution of concentration 5% (m/V). What is the mass of the solute contained in this bottle?

7. Ways of Expressing Concentration As % (m/m) 8 % (m/m) means “ 8 g of solute dissolved in 100g of solution” To solve problems, set up a ratio and cross multiply

8. % (m/m) Example 30 g of Kool- Aid are dissolved in 500 mL of water. What is the concentration of this solution expressed as % (m/m)

9. % (m/m) Example A solution was made using 8g of solute and it has a concentration of 6% (m/m). What is the mass of the solution?

10. Ways of Expressing Concentration As % (V/V) 10% (V/V) means “10 mL of solute dissolved in 100mL of solution” To solve problems, set up a ratio and cross multiply

11. % (V/V) Example A 750 mL bottle of wine contains 90 mL of alcohol. What is the alcohol concentration of this wine? ( in %(V/V))

12. % (V/V) Example Vinegar is really just 5% (V/V) acetic acid. What volume of acetic acid is contained in a 600 mL bottle of vinegar

13. Ways of Expressing Concentration In ppm (parts per million) 125 ppm means “125 g of solute in 1 000 000g of solution” We use ppm to express very small concentrations. To solve problems, set up a ratio and cross multiply

14. ppm Example A certain brand of bottled water contains 25 ppm of chlorine ions. How many grams of chlorine ions are present in a bottle that contains 500 mL?

15. ppm Example What is the concentration (in ppm) of a 200g sample of soil that contains 0.01g of lead?