Final answer:
To determine the mass percent of FeCl3 in a solution with a density of 1.42 g/ml and a molarity of 1.19 molar, first calculate the mass of FeCl3 per liter (1.19 mol/L x 162.2 g/mol = 193.018 g) and then divide by the mass of the solution per liter (1420 g) and multiply by 100%, resulting in a mass percent of 13.59%.
Step-by-step explanation:
To find the mass percent of FeCl3 in a solution with a density of 1.42 g/ml and a molarity of 1.19 molar, we need to calculate the mass of FeCl3 in 1 liter of solution and compare it to the total mass of the solution. Using the molar mass of FeCl3, which is approximately 162.2 g/mol (56 g/mol for Fe + 3 x 35.45 g/mol for Cl), we first convert the molarity to mass by multiplying the molarity by the molar mass:
Molar Mass of FeCl3 = 162.2 g/mol
Mass of FeCl3 per liter = Molarity x Molar Mass
= 1.19 mol/L x 162.2 g/mol
= 193.018 g
Since the density of the solution is 1.42 g/ml, the mass of 1 liter of solution is:
Mass of the solution per liter = 1000 ml x 1.42 g/ml
= 1420 g
Now, we calculate the mass percent of FeCl3:
Mass percent of FeCl3 = (Mass of FeCl3 / Mass of the solution) x 100%
= (193.018 g / 1420 g) x 100%
= 13.59%
To conclude, the mass percent of FeCl3 in this solution is 13.59%.