How would you prepare 150.0 mL of a 0.200 M aqueous solution of potassium chloride from a 0.500 M aqueous solution of potassium chloride?
A)Add 60.0 mL of water to the 0.500 M solution.
B)Take 60.0 mL of the 0.500 M solution and add enough water to complete to 150.0 mL of solution.
C)Add 90.0 mL of water to the 0.500 M solution.
D)Take 90.0 mL of the 0.500 M solution and add enough water to complete to 150.0 mL of solution.

Question

Quizplus · Accepted Answer

To prepare a 0.200 M solution from a 0.500 M solution, you use the dilution formula $C_1V_1 = C_2V_2$. Here, $C_1 = 0.500 \, M$, $V_1$ is what we're solving for, $C_2 = 0.200 \, M$, and $V_2 = 150.0 \, mL$. Solving for $V_1$ gives $V_1 = \frac{C_2V_2}{C_1} = \frac{0.200 \times 150.0}{0.500} = 60.0 \, mL$. You take 60.0 mL of the 0.500 M solution and add enough water to make the volume up to 150.0 mL.

How Would You Prepare 150