The haemoglobin from the red blood corpuscles of most mammals contains approximately `0.33%` of iron by weight. The molecular weight of haemoglobin as `67,200`.
The number of iron atoms in each molecule of haemoglobin is (atomic weight of iron `=56`):

Options

A. `3`
B. `4`
C. `2`
D. `6`

Answer

B

Explanation

100 g haemoglobin has = 0.33 g Fe
67200 g haemoglobin has Fe
`= (0.33)/(100)xx67200=221.76g`
1 mole of `N_(0)` molecules of haemoglobin has `= (221.76)/(56)`g atom of Fe
`= 3.96` g-atom of `Fe ~= 4.0 g` atoms