Question

Haemoglobin contains 0.25 % iron by mass. The molecular mass of haemoglobin is 89600. Calculate the number of iron atoms per molecule of haemoglobin.

Answer 1

Correct Answer - 4
100 g of haemoglobin has iron = 0.25 g
89600 g of haemoglobin has iron `= (0.25g)xx((89600g))/((100g))=224g`
No. of gram atoms of iron (Fe) `= ((224g))/((56g))=4g` atom
Thus, 1 gram mole of haemoglobin has Fe atoms = 4g atom
`:.` 1 molecule of haemoglobin has Fe atoms = 4.