Hemoglobin (Hb) contains 0.33% of iron by weight. The molecular weight of Hb is approximately 67200. The number of iron atoms (At. Wt. of Fe=56) prese

The formulae of calculating the percentage of Fe is 0.33 % molecular weight of hemoglobin

Weight of Fe present =   0.33/100 × 67200 = 221.8

One Fe weighs 55.8 g

Thus, the number of atoms in one molecule of hemoglobin is  221.8/55.8 =4

Final Answer: Hence, the correct answer is (B) 4.