Question

If you have 100 mL of 20% hydrochloric acid, how many mL of 4% HCl can you make?

A) 500 mL
B) 1000 mL
C) 50 mL
D) 250 mL

Answer 1

By using the dilution formula C1V1 = C2V2, it's calculated that 500 mL of 4% HCl can be made from 100 mL of 20% HCl.

Step-by-step explanation:

To determine how many mL of 4% HCl can be made from 100 mL of 20% HCl, we can use the concept of dilution. The amount of solute in the solution remains constant during dilution. The formula to use for dilution is C1V1 = C2V2, where C1 and V1 are the concentration and volume of the initial solution, and C2 and V2 are the concentration and volume of the final solution. Given that we have C1 = 20% and V1 = 100 mL, and we want to find V2 when C2 = 4%, we can rearrange the formula to solve for V2: V2 = (C1V1)/C2.

Substituting in our known values gives us V2 = (20% * 100 mL) / 4% = 2000% mL / 4% = 500 mL. Therefore, you can make 500 mL of 4% HCl from 100 mL of 20% HCl, which corresponds to option A.