Question

Hemoglobin (C₇₃₈H₁₁₆₆N₈₁₂O₂₀₃Fe) is a substance found in the red blood cell and is responsible for the absorption of Oxygen gas into our bloodstream by binding oxygen to the iron. Based on the chemical composition of the hemoglobin, how many percent of the substance is made up of iron? 

Answer 1

Molar mass of Haemoglobin= (12x738) + (1x1166) + (14x812) + (16x203) + 56= 24694

Percentage by mass of Fe= 56/24694 x 100% = 0.23%