Question

You need 520. mL of a 10. % (m/v) glucose solution. If you have a 25% (m/v) glucose solution on hand, how many milliliters do you need

Answer 1

Answer:

The answer is "208 mL".

Explanation:

$C_1 = 25\% \ \frac{m}{v}\\\\C2 = 10\% \ \frac{m}{v}\\ \\V_1= 520\ \ mL\\\\V_2=?$

In dilutions of different concentration, its initial volume for glucose solution V1 can be obtained by using the following formula, i.e.

$\to C_1V_1 = C_2V_2\\\\\to V_1 = \frac{C_2V_2}{C_1} \\\\= \frac{10 \times 520 }{ 25}\\\\ = 208 \ mL$

The solution of 520 mL $10\%\ \ (\frac{m}{v})$ final glucose solution thus requires 208 mL of glucose solution of $25\%\ \ (\frac{m}{v})$.