Question

Hemoglobin Contains 0.25% Iron By Mass. The Molecular Mass Of Hemoglobin Is 89600. Calculate The Number Of Iron Atoms Per Molecule Of Hemoglobin.

[$\mathrm{Atomic}\mathrm{mass}\mathrm{of}\mathrm{Fe}=56$]

Answer 1

• The iron percentage is 0.25%.

If there are 0.25 grams of iron in 100 grams of haemoglobin, then 89600 will have:

$$\begin{gathered} \Rightarrow 89600\times \frac{0.25}{100} \\ \Rightarrow 89600\times 0.0025 \\ \Rightarrow 224\mathrm{gm} \\ \mathrm{Atomic}\mathrm{weight}\mathrm{of}\mathrm{Fe}=56 \\ \mathrm{Number}\mathrm{of}\mathrm{moles}=\frac{224}{56} \\ =4 \end{gathered}$$

Hence, the number of Iron atoms per molecule of Haemoglobin is 4.