TeXes Science Practice Test

Which of the following best describes an 8% solution?

1. The solute constitutes 8 grams per 100 mL of solution

2. The solution is made with 8 moles of solute

3. The solvent is 8% by volume

4. The pH level is 8

The correct answer is: The solute constitutes 8 grams per 100 mL of solution

An 8% solution indicates that there are 8 grams of solute present for every 100 mL of the entire solution. This concentration is a common way to express the amount of solute relative to the volume of the solution, making it easier to understand and prepare various solutions in a laboratory setting. This percentage is often used in chemistry and biology to specify dilutions, as it provides a clear and measurable standard for creating consistent concentrations. The other options do not accurately describe an 8% solution. While it is possible to refer to a concentration in terms of moles, stating 8 moles does not specify a volume and cannot be understood the same way as weight per volume percentage. Mentioning the solvent as 8% by volume does not convey the information about the solute, which is the key concept for an 8% solution. Lastly, a pH level of 8 indicates the acidity or basicity of a solution but does not relate to the concentration of the solute in the solution. Therefore, the description that provides the correct understanding of an 8% solution is that it consists of 8 grams of solute per 100 mL of solution.