Hemoglobin is the oxygen carrying molecule of red bloods and contains 4 atoms of iron per molecule of hemoglobin. A sample of hemoglobin weighing 13.4 g contains 45.6 mg iron. What is the molecular mass of hemoglobin?
I'm unsure of where to begin with this problem. I know g/mol = amu so I've been trying to get the molar mass to know the molecular mass.
Please explain, thanks!
mols Fe = grams Fe/atomic mass Fe.
mols hemoglobin = 1/4 that since there are 4 atoms/molecule
mols hemoglobin = grams/molar mass. You know grams ad mols, solve for molar mass. I get something like 65,000 give or take a little.
To find the molecular mass of hemoglobin, you need to calculate the molar mass of hemoglobin. The molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol).
First, let's calculate the moles of iron in the sample of hemoglobin. We are given that the sample contains 45.6 mg of iron. To convert this to grams, divide by 1000:
45.6 mg ÷ 1000 = 0.0456 g
Next, we need to find the number of moles of iron. To do this, we divide the mass of iron by its molar mass. The molar mass of iron is 55.845 g/mol.
0.0456 g ÷ 55.845 g/mol = 0.0008167 mol
Now, we know that there are 4 iron atoms per molecule of hemoglobin. Therefore, the number of moles of hemoglobin is four times the number of moles of iron:
0.0008167 mol × 4 = 0.0032668 mol
Finally, to find the molecular mass of hemoglobin, we divide the mass of hemoglobin by the number of moles of hemoglobin:
Molar mass = mass of hemoglobin / number of moles of hemoglobin
Since the mass of hemoglobin is 13.4 g and the number of moles of hemoglobin is 0.0032668 mol:
Molar mass = 13.4 g / 0.0032668 mol
Calculating this, we get:
Molar mass ≈ 4105.89 g/mol
So the molecular mass of hemoglobin is approximately 4105.89 g/mol.