Lisa, a librarian at the Knights of Favonius, is also a great potion maker. She wants to create a potion containing potassium dichromate (K2Cr2O7). The only available solutions in her laboratory are 25.0 mL of 0.650 M solution and 18.0 mL of 0.350 M solution.   What is the concentration of potassium dichromate (in M) when the two solutions are combined? What is its concentration in % w/v? For this potion to have a stronger effect, Lisa wants it to have a concentration of 20.0 % w/v. Can she create it based on combining the available solutions alone? Lisa only settled to produce the lesser potent potion with 10.0 % w/v. How much water will she add (in mL) to achieve this concentration?

Lisa, a librarian at the Knights of Favonius, is also a great potion maker. She wants to create a potion containing potassium dichromate (K₂Cr₂O₇). The only available solutions in her laboratory are 25.0 mL of 0.650 M solution and 18.0 mL of 0.350 M solution.

1. What is the concentration of potassium dichromate (in M) when the two solutions are combined?
2. What is its concentration in % w/v?
3. For this potion to have a stronger effect, Lisa wants it to have a concentration of 20.0 % w/v. Can she create it based on combining the available solutions alone?
4. Lisa only settled to produce the lesser potent potion with 10.0 % w/v. How much water will she add (in mL) to achieve this concentration?