Question

A student pipets 10 ml of a 0.0693 m solution of kbr into a 500 ml volumetric flask and dilutes to the mark. what is the concentration of the resulting solution?

Answer 1

The initial concentration of solution is 0.0693 M. The volume of solution taken is 10 mL and it is diluted to a final volume of 500 mL.

According to dilution law, the product of initial concentration and volume is equal to the product of final concentration and volume as follows:

`C_(1)V_(1)=C_(2)V_(2)`

Here,
`C_(1)` is initial concentration,
`C_(2)` is final concentration,
`V_(1)` is initial volume and
`V_(2)` is final volume.

Rearranging to calculate final concentration,

`C_(2)=(C_(1)* V_(1))/(V_(2))`

Putting the values,

`C_(2)=(0.0693 M* 10 mL)/(500 mL)=0.001386 M`

Therefore, concentration of the resulting solution is 0.001386 M.