Stock solution A is prepared by dissolving 182 mg of ferrous ammonium sulfate in water and diluting to volume in a 500-mL volumetric flask. Calculate the concentration of iron, in ppm, in stock solution A.

percent Fe in Fe(NH4)2(SO4)2.6H2O Note this is the common hydrated salt, if different, you need to recalculate.

percentFe=2*55.8/392
mass iron in 182g= percentFe*182=51.8mg
concentration 51.8mg/500g or 51.8mg/500e3mg or 51.8/.5e6 or 10.3 ppm

To calculate the concentration of iron in parts per million (ppm) in stock solution A, we need to determine the amount of iron in the solution and then convert it to ppm.

1. Calculate the amount of iron (Fe) in stock solution A:
- The molecular weight of ferrous ammonium sulfate is: Fe(NH₄)₂(SO₄)₂•6H₂O
= 55.85 g/mol (Fe) + 2 * (14.01 g/mol (N) + 4 * 1.01 g/mol (H)) + 2 * (32.06 g/mol (S) + 4 * 16.00 g/mol (O)) + 6 * 18.02 g/mol (H₂O)
= 55.85 g/mol + 2 * (14.01 g/mol + 4.04 g/mol) + 2 * (32.06 g/mol + 64.00 g/mol) + 108.12 g/mol
= 392.14 g/mol
- Now, calculate the moles of ferrous ammonium sulfate (Fe(NH₄)₂(SO₄)₂•6H₂O) in 182 mg:
Moles = mass / molar mass
Moles = 0.182 g / 392.14 g/mol

2. Calculate the concentration of iron in the solution:
- The volume of the stock solution is given as 500 mL.
- Concentration (in ppm) = (moles of Fe / volume of solution) * (1,000,000 ppm / 1 mol/L)

Let's plug in the values and calculate the concentration of iron in stock solution A in ppm:

Concentration (in ppm) = (0.182 g / 392.14 g/mol) / (0.5 L) * (1,000,000 ppm / 1 mol/L)

To calculate the concentration of iron in ppm (parts per million) in stock solution A, we need to know the molar mass of ferrous ammonium sulfate and the volume of the stock solution.

Let's break down the process step by step:

Step 1: Calculate the number of moles of ferrous ammonium sulfate.
The molar mass of ferrous ammonium sulfate (Fe(NH4)2(SO4)2) is:
Iron (Fe): atomic mass = 55.845 g/mol
Ammonium (NH4): atomic mass = 18.038 g/mol
Sulfate (SO4): atomic mass = 96.06 g/mol

Ferrous ammonium sulfate has two iron atoms, so we calculate the molar mass as follows:
Molar mass of ferrous ammonium sulfate = (2 x 55.845) + (2 x 18.038) + 96.06 = 392.14 g/mol

Now, we can calculate the number of moles of ferrous ammonium sulfate dissolved in the stock solution:
182 mg = 0.182 g
Number of moles = mass (in grams) / molar mass
Number of moles = 0.182 g / 392.14 g/mol = 0.000464 mol

Step 2: Calculate the volume of the stock solution A in liters.
The stock solution is prepared in a 500-mL volumetric flask, which is equal to 0.5 liters.

Step 3: Calculate the concentration in ppm.
Concentration (in ppm) = (moles / volume in liters) x 10^6
Concentration (in ppm) = (0.000464 mol / 0.5 L) x 10^6 = 928 ppm

Therefore, the concentration of iron in stock solution A is 928 ppm.