Final answer:
To make a 3.0 M HCl solution from a concentrated 12.1 M HCl solution, you will need approximately 24.79 mL of the concentrated solution.
Step-by-step explanation:
To make a 3.0 M HCl solution, you will need to dilute the concentrated 12.1 M HCl solution. The formula for dilution is:
C1V1 = C2V2
Where C1 is the initial concentration, V1 is the initial volume, C2 is the final concentration, and V2 is the final volume.
In this case, C1 = 12.1 M, V1 = ? (unknown), C2 = 3.0 M, and V2 = 100.0 mL. Rearranging the formula, we get:
V1 = (C2 * V2) / C1
Substituting the values, we can calculate the volume of 12.1 M HCl needed to make 100.0 mL of a 3.0 M HCl solution:
V1 = (3.0 M * 100.0 mL) / 12.1 M
V1 = 24.79 mL
So, you will need approximately 24.79 mL of the concentrated HCl solution to make 100.0 mL of a 3.0 M HCl solution.