what is the percentage by mass of solution formed by dissolving 27.0 grams of hcl in 102.0 grams of…

Explanation:

Step1: Calculate mass of solution

Mass of solution = mass of solute + mass of solvent. Here, mass of solute (HCl) is 27.0 g and mass of solvent (water) is 102.0 g. So, mass of solution = 27.0 + 102.0 = 129.0 g.

Step2: Calculate mass - percentage

Mass - percentage = $\frac{\text{mass of solute}}{\text{mass of solution}}\times100%$. Substitute mass of solute = 27.0 g and mass of solution = 129.0 g. Mass - percentage = $\frac{27.0}{129.0}\times100% \approx 20.9%$.

Answer:

B. 20.9%