Final answer:
The concentration of the solution prepared by dissolving 25.0 g of sugar into 100.0 g of water is calculated as mass/mass percent. The sum of the solute and solvent masses is 125.0 g, resulting in a 20% sugar concentration.
Step-by-step explanation:
Calculating Concentration of a Sugar Solution
To calculate the concentration of the solution prepared by dissolving 25.0 g of sugar into 100.0 g of water, we need to determine the mass/mass percent concentration. The mass of solution is the sum of the mass of the solute (sugar) and the mass of the solvent (water). In this case, the mass of solution equals 25.0 g + 100.0 g, which is 125.0 g.
Mass/mass percent concentration is calculated as:
Mass percent = (mass of solute / mass of solution) x 100%
Substituting in the given masses:
Mass percent = (25.0 g / 125.0 g) x 100% = 20%
This means that the concentration of sugar in the solution is 20%. This is the mass of sugar divided by the total mass of the solution, multiplied by 100 to express it as a percentage.