Question

How would you prepare 500mL of 0.5 M solution using your stock solution?

Answer 1

We have a stock solution with an initial concentration of 1.0M, this will be C1. We are asked to find the volume (V1) that we must take from the stock solution to obtain a final solution with a concentration, C2 equal to 0.5M. The final volume (V2) must be equal to 500mL.

Now, we will apply the dilution equation to find the volume that we should take from the stock solution:

`C_1V_1=C_2V_2`

We clear V1 and replace the following values:

C1= 1.0M

C2=0.5M

V2=500mL

V1= ?

`V_1=(C_2V_2)/(C_1)`
`V_1=(0.5M*500mL)/(1.0M)=250mL`

Answer: Therefore, to prepare the told solution we must take 250 mL of the 1.0M stock solution and complete the rest of the solution with water until completing 500mL