why does iron present in our body does not rust
Answers
Actually there is “rust” when oxygen binds to hemoglobin.
As you may have probably heard before, oxygenated blood and deoxygenated blood have a slightly different color; oxygenated blood tends to have a brighter red color and deoxygenated blood takes on a bit of a darker, deeper red color. Iron in the blood is oxidized when it binds Oxygen, which is similar to what happens on car bumpers and chain-linked fences. The oxidation, or rusting, of Iron in hemoglobin gives oxygenated blood its brighter red color.
If you're still wondering why our arteries aren't filled with crusty, orange crumbs then I'd answer your question by telling you that there isn't nearly enough Iron in our body to form in that manner. For 4 Iron molecules per hemoglobin, about 270,000,000 hemoglobin per red blood cell, and 20–30 billion (averaged to 25) RBCs in an adult, one could calculate that there is a total of about 2.5 g of Iron in about 5L of blood (approximately the mass of a dime dispersed amongst 5L). Even if the Iron in our blood was free floating, the iron would not rust as it does on a car bumper.