Dilution and Concentration Problems

This video tutorial covers dilution problems, focusing on the m1v1=m2v2 equation. It explains how to decrease concentration by adding water and increase it by adding solute or through evaporation. The tutorial includes several example problems, demonstrating calculations for dilution, evaporation, and mixing solutions. It also covers the concept of weighted averages when mixing solutions with the same substance.

What is the equation used to solve dilution problems?

• m1v1 = m2v2

• c1v1 = c2v2

• p1v1 = p2v2

• d1v1 = d2v2

How can you decrease the concentration of a solution?

• Add more solute

• Add water

• Increase temperature

• Decrease pressure

What happens to the concentration if you double the volume of a solution?

• It remains the same

• It halves

• It doubles

• It triples

In a dilution problem, if the original concentration is 0.8 M and the new concentration is 0.2 M, by what factor has the volume increased?

• 4

• 3

• 5

• 2

How much water was removed if the volume decreased from 300 mL to 100 mL?

• 200 mL

• 100 mL

• 300 mL

• 400 mL

What is the new volume of a solution if 350 mL of water is added to 225 mL of a solution?

• 500 mL

• 550 mL

• 575 mL

• 600 mL

When mixing two solutions, what happens to the concentration of each if the total volume increases?

• Concentration doubles

• Concentration remains the same

• Concentration decreases

• Concentration increases

What is the final concentration of NaCl if 60 mL of 0.8 M NaCl is mixed with 80 mL of 0.5 M KBr?

• 0.286 M

• 0.343 M

• 0.5 M

• 0.4 M

What is the new concentration of a mixture if 150 mL of 0.6 M CaCl2 is mixed with 300 mL of 0.9 M CaCl2?

• 0.85 M

• 0.75 M

• 0.8 M

• 0.7 M

If two solutions with the same substance are mixed, how is the final concentration determined?

• By subtracting the concentrations

• By adding the concentrations

• By taking the weighted average

• By taking the average