Question

Suppose you needed a 0.0250 M sodium thiosulfate solution to conduct 6 titrations. Explain how you would make up this solution using a 0.4782 M stock solution of sodium thiosulfate. Include all necessary measured quantities, lab techniques and the glassware you would use.

Answer 1

Explanation:

According to the law of dilution,

       $M_{1}V_{1} = M_{2}V_{2}$

The given data is as follows.

   $M_{1}$ = 0.4782,     $V_{1}$ = ?

    $M_{2}$ = 0.025 ,    $V_{2}$ = 250 mL

Hence, we will calculate the value of $V_{1}$ as follows.

              $V_{1} = \frac{M_{2} \times V_{2}}{M_{1}}$

                          = $\frac{0.025 \times 250}{0.4782}$

                          = 13.07

Thus, we can conclude that we need 13.07 mL 0.4782 M sodium thiosulfate solution using pipette.