Question

Haemoglobin contains 0.33% of iron by weight. The molecular weight of haemoglobin is approximately 67200. The number of iron atoms (At. wt. of Fe = 56) present in one molecule of haemoglobin is _____.

(A) 1 

(B) 2 

(C) 4 

(D) 6

Answer 1

Correct option: (C) 4

100 g of haemoglobin contains 0.33 g of Fe

∴ 67200 g of haemoglobin contains

\(\cfrac{67200\, \times\, 0.33}{100}\)

= 221.76 g of Fe.

Number of atoms of Fe = \(\cfrac{221.76}{56}\)

= 3.96 ≈ 4