Final answer:
To dilute a 60% acid solution to a 50% acid solution, 65 mL of water should be added to the existing 65 mL of acid.
Step-by-step explanation:
To dilute a 60% acid solution to a 50% acid solution, we need to add a certain volume of water to the existing 65 mL of acid. The concentration of a solution is given by the ratio of the volume of solute (in this case acid) to the total volume of the solution, including the solvent (water).
Let's define the volume of water to be added as V mL. After adding water, the new total volume of the solution will be V mL + 65 mL. To maintain a 50% concentration of acid, the volume of acid (which remains 65 mL) should be 50% of the total volume. To find V, we can set up the equation:
65 mL / (V mL + 65 mL) = 50 / 100
Now, we solve for V:
- 0.50 = 65 / (V + 65)
- 0.50 * (V + 65) = 65
- 0.50V + 32.5 = 65
- 0.50V = 65 - 32.5
- 0.50V = 32.5
- V = 32.5 / 0.5
- V = 65 mL
Therefore, to dilute the 65 mL of 60% acid solution to a 50% acid solution, 65 mL of water should be added.