Final answer:
To find the percent by mass of NaCl in a 1.22 M solution with a density of 1.06 g/mL, calculate the mass of NaCl using its molar mass, the mass of the solution using its density, and then the ratio of these masses multiplied by 100. The solution contains 6.72% NaCl by mass.
Step-by-step explanation:
To find the percent by mass of sodium chloride (NaCl) in a 1.22 M solution with a density of 1.06 g/mL, we first need to calculate the mass of NaCl present in a known volume of the solution and the mass of the solution itself. Using the molar mass of NaCl, which is 58.44 g/mol, we can determine the mass of NaCl in one liter of solution (since molarity is moles/L).
The calculation is as follows: 1.22 moles/L × 58.44 g/mol = 71.30 g of NaCl per liter of solution. To get the mass of the solution, we use its density: 1 liter × 1.06 g/mL × 1000 mL/L = 1060 g. Finally, to find the percent by mass, we use the formula:
(Mass of NaCl / Mass of solution) × 100 = (71.30 g / 1060 g) × 100 = 6.72%
Therefore, the percent by mass of NaCl in the solution is 6.72%.