Question

In order to prepare 50.0 mL of 0.200 M HCl you will add _____ mL of 1.00 M HCl to _____ mL of water

Answer 1

To solve this problem, we have to find the volume of 1.00M HCl solution we have to add.

To do it, we have to use the formula for dilutions:

`V1C1=V2C2`

Where V1 is the initial volume, in this case it is unknown; C1 is the initial concentration that in this case is 1.00M; V2 is the final volume, that is 50.0mL and C2 is the final concentration that is 0.200M.

Solve the equation for V1 and replace for the given values:

`V1=(V2C2)/(C1)`
`\begin{gathered} V1=(50.0mL\cdot0.200M)/(1.00M) \\ V1=10.0mL \end{gathered}`

It means that we have to add 10.0mL of 1.00M HCl.

To find the volume of water, substract the initial volume of HCl to the final volume:

`Vw=50.0mL-10.0mL=40mL`

It means that the 10.0mL of HCl have to be added to 40mL of water.