Chapter 14.2, Problem 13PP

Interpretation Introduction

Interpretation:

Percent by volume of ethanol in a solution containing $35mL$ ethanol dissolved in $155mL$ water is to be calculated.

Concept introduction:

The concentrations of solutions are expressed in different ways, all of them involved in the quantity of solute and the quantity of solution or solvent. Among them, Volume/volume percentage (v/V percent) is used to express the concentration of solution.

Volume/volume percentage (v/V percent):

Percent by volume usually describes solutions in which both solute and solvent are liquids. It is expressed as the ratio of the volume of the solute to the total volume of the solution multiplied by 100.

In expression (v/V) % $=\frac{Volumeofsolute}{Volumeofsolution}\times 100$

Answer to Problem 13PP

Percent by volume of ethanol in a solution having $35mL$ ethanol dissolved in $155mL$ water is $18.4\%$

Explanation:

(v/V) % $=\frac{Volumeofsolute}{Volumeofsolution}\times 100$

If we write in equation,

Percent by volume of ethanol = $\frac{Volumeofethanol}{Volumeofsolution}\times 100$

Data given: volume of ethanol = $35mL$

Volume of water = $155mL$

So, volume of the solution = volume of ethanol + volume of water

$\begin{array}{l}=35mL+155mL\\ =190mL\end{array}$

Percent by volume of ethanol = $\frac{Volumeofethanol}{Volumeofsolution}\times 100$

$=\frac{35}{190}\times 100$

= $18.4\%$

Percent by volume of ethanol in a solution having $35mL$ ethanol dissolved in $155mL$ water is $18.4\%$

Explanation of Solution

(v/V) % $=\frac{Volumeofsolute}{Volumeofsolution}\times 100$

If we write in equation,

Percent by volume of ethanol = $\frac{Volumeofethanol}{Volumeofsolution}\times 100$

Data given: volume of ethanol = $35mL$

Volume of water = $155mL$

So, volume of the solution = volume of ethanol + volume of water

$\begin{array}{l}=35mL+155mL\\ =190mL\end{array}$

Percent by volume of ethanol = $\frac{Volumeofethanol}{Volumeofsolution}\times 100$

$=\frac{35}{190}\times 100$

= $18.4\%$

Conclusion

Percent by volume of ethanol in a solution having $35mL$ ethanol dissolved in $155mL$ water is $18.4\%$