Question

In the lab, Chris has two solutions that contain alcohol and is mixing them with each other. Solution A is 40% alcohol and Solution B is 10% alcohol. He uses 1200 milliliters of Solution A. How many milliliters of Solution B does he use, if the resulting mixture is a 30 % alcohol solution?

Answer 1

To determine the volume of Solution B needed to obtain a 30% alcohol solution, set up an equation using the volume percentage concept. Solve for the unknown volume of Solution B by simplifying the equation and isolating the unknown variable. The volume of Solution B required is 600 mL.

Step-by-step explanation:

To solve this problem, we can use the concept of the volume percentage of a solution. The volume percentage is the volume of solute divided by the volume of the solution, multiplied by 100%. In this case, we want to find the volume of Solution B, so we can set up the following equation:

Volume of alcohol in Solution A + Volume of alcohol in Solution B = Total volume of alcohol in the mixture

0.4 * 1200 mL + 0.1 * Volume of Solution B = 0.3 * (1200 mL + Volume of Solution B)

Simplifying the equation, we have:

480 mL + 0.1 * Volume of Solution B = 360 mL + 0.3 * Volume of Solution B

Subtracting 0.1 * Volume of Solution B from both sides, we get:

480 mL = 360 mL + 0.2 * Volume of Solution B

Subtracting 360 mL from both sides, we have:

120 mL = 0.2 * Volume of Solution B

Dividing both sides by 0.2, we find:

Volume of Solution B = 600 mL