Question

The red colour of blood is due to a
compound called “haemoglobin”. It
contains 0.335 % of iron. Four atoms
of iron are present in one molecule of
haemoglobin. What is its molecular
weight?
(At. mass : Fe 55.84)
​

Answer 1

Hemoglobin contains 4 Fe atoms so basically 55.85 atomic mass of Fe x 4 = 223.4 a.m.u

so its 0.335 % of 223.4 will give us the molar mass of haemoglobin.

(4 x Fe atomic mass) / molar mass of hemoglobin = 0.335%

223.4 / molar mass of hemoglobin = 0.00335

molar mass of hemoglobin = 66687 (66,687) g