Q.9.97 - An Introduction to General, Organic, and Biological Chemistry

Question

How many liters of $12\% (\mathrm{m}/\mathrm{v})$ $\mathrm{KOH}$ solution would you need to obtain $75 \mathrm{g}$ of glucose?

Step-by-Step Solution

Answer

The volume of the solution is $0.716 \mathrm{L}$.

Step 1: Given information

The percentage of KOH solution is given which is $12 \%$.

Step 2: Explanation

Molarity is defined as the ratio of concentration over volume.

The percentage of KOH solution is given which is $12 \%$ $\left(\mathrm{w}/\mathrm{v}\right)$, it means that $12 \mathrm{gm}$ of $\mathrm{KOH}$ is present in $100 \mathrm{mL}$ of water.

Therefore, for 86 g of KOH, the volume will be

$\frac{86 \cancel{\mathrm{gm}}}{12 \cancel{\mathrm{gm}}}\times 100=7.166\times 100=716.66 \mathrm{mL}$

The unit conversion for mL into L is given as follows:

$716.66 \cancel{\mathrm{mL}}\times \frac{1 \mathrm{L}}{1000 \cancel{\mathrm{mL}}}=0.716 \mathrm{L}$

Thus, the volume of the solution is $0.716 \mathrm{L}$.