A 1.00 L sample of water contains 0.0036 g of Cl^⁻ ions.Determine the concentration of chloride ions in ppm if the density of the solution is 1.00 g/mL. A)2.8 ppm B)7.2 ppm C)3.6 ppm D)1.8 ppm E)5.4 ppm

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Quizplus · Accepted Answer

First, we need to find the total amount of chloride ions in the solution: 0.0036 g Cl^⁻ × (1 mol Cl^⁻ / 97.0 g Cl^⁻) = 3.71 × 10⁻⁵ mol Cl^⁻ Since the solution has a density of 1.00 g/mL and a volume of 1.00 L, its mass is 1000 g, so the concentration of chloride ions is: (3.71 × 10⁻⁵ mol Cl⁻) / (1000 g H₂O) × (1 × 10⁶ ppm / 1 mol) = 3.71 × 10⁻² ppm = 3.6 ppm (to two significant figures) Therefore, the best choice is C, 3.6 ppm.

A 100 L Sample of Water Contains 0