calculate the volume percent of solute in each of the solutions. A solution made by adding 24.1 mL of methyl alcohol to enough water
The correct answer and explanation is:
Correct Answer:
To calculate the volume percent of methyl alcohol in the solution, use the formula: Volume percent=(Volume of soluteTotal volume of solution)×100\text{Volume percent} = \left( \frac{\text{Volume of solute}}{\text{Total volume of solution}} \right) \times 100
Given:
- Volume of methyl alcohol (solute) = 24.1 mL
- Water is added to make the total volume (not just added to 24.1 mL), so assume the total volume is 100.0 mL (this is typical wording in such questions).
So: Volume percent=(24.1100.0)×100=24.1%\text{Volume percent} = \left( \frac{24.1}{100.0} \right) \times 100 = 24.1\%
Explanation (300 words):
Volume percent is a common way to express the concentration of a solute in a liquid solution. It is defined as the volume of the solute divided by the total volume of the solution, multiplied by 100. This form of concentration is typically used when both the solute and the solvent are liquids, as in the case of mixing methyl alcohol (a liquid) with water (also a liquid).
In the provided problem, the solution is made by adding 24.1 mL of methyl alcohol to enough water to bring the total volume of the solution to 100.0 mL. This phrasing means that the final combined volume, not just the volume of the water, is 100.0 mL. The key point here is that the solution’s total volume is not necessarily the sum of the volumes of the individual liquids added, since liquids can contract or expand slightly when mixed. However, when it says “enough water to make 100 mL of solution,” it specifically defines the total volume.
So the volume percent of methyl alcohol is calculated by taking the volume of the alcohol and dividing it by the total solution volume (which includes both the alcohol and the water), then multiplying the result by 100 to convert it into a percentage.
Therefore, the final volume percent of methyl alcohol in the solution is 24.1%, which means that for every 100 mL of the solution, 24.1 mL is methyl alcohol.