Final answer:
To determine the mass percent of a citric acid solution, calculate the mass of citric acid in a volume based on molarity, then divide by the total mass of the solution (obtained from volume and density) and multiply by 100.
Step-by-step explanation:
The student has asked for the mass percent of a citric acid solution with a given concentration and density. To calculate the mass percent, we must first determine the mass of the citric acid in a certain volume of the solution and then divide it by the total mass of that volume of solution. Since the solution has a density of 1.10 g/mL, we can calculate the mass of a given volume using this density. For example, the mass of 1.00 liter (1000 mL) of this solution is 1000 mL × 1.10 g/mL = 1100 g. Given that the citric acid solution is 1.37 M (molar), this means there are 1.37 moles of citric acid per liter of solution. The molar mass of citric acid (H3C6H5O7) must be calculated by summing the atomic masses of its constituent elements. Once we have the molar mass, it can be multiplied by the number of moles to get the mass of citric acid in grams.
To find the mass percent, the formula used is: (mass of solute / mass of solution) × 100. You will solve for the mass of the citric acid in the solution and then divide it by the total mass (mass of solution) which we determined earlier (1100 g), and then multiply the quotient by 100 to get the mass percent.