Final answer:
To convert 0.0750 M HCl to ppm w/w, multiply the mass of HCl per liter of solution (2.7345 g) by 1,000,000 and divide by the total mass of the solution (1004.9 g), resulting in approximately 2722 ppm.
Step-by-step explanation:
To calculate the concentration of HCl in ppm w/w (parts per million, weight/weight), we must first understand what this concentration means. It indicates how many parts of a substance there are in a million parts of the total solution.
Given a 0.0750 M HCl solution, we know the molarity (M) is moles of solute per liter of solution. To convert this to ppm, we follow these steps:
- Calculate the mass of 1 mole of HCl. HCl has an approximate molar mass of 36.46 g/mol.
- For a 0.0750 M solution, in 1 liter of solution, there is 0.0750 moles of HCl. Multiply the number of moles by the molar mass to find the mass of HCl in grams: 0.0750 mol × 36.46 g/mol = 2.7345 g.
- Determine the mass of 1 liter of solution using the density provided. 1 L is equivalent to 1000 mL, so the mass in grams is 1000 mL × 1.0049 g/mL = 1004.9 g.
- Now, convert the mass of HCl to ppm w/w: (mass of solute/mass of solution) × 1,000,000 = (2.7345 g / 1004.9 g) × 1,000,000 ≈ 2722 ppm.
Therefore, the concentration of the 0.0750 M HCl solution in ppm w/w is approximately 2722 ppm.