Question

What is the molarity of a NaCl stock used to make 750 ml of a dilute 10 mM solution if 5 ml of the concentrated solution was used?

Answer 1

Explanation:

The given data is as follows.

          $M_{1}$ = 10 mM = $10 \times 10^{-3}$ M

          $V_{1}$ = 750 ml,           $V_{2}$ = 5 ml

          $M_{2}$ = ?

Therefore, calculate the molarity of given NaCl stock as follows.

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

                  $10 \times 10^{-3} \times 750 ml = M_{2} \times 5 ml$

                   $M_{2}$ = 1.5 M

Thus, we can conclude that molarity of given NaCl stock is 1.5 M.