Why does blood turn red when hits oxygen?

Answer 1

Theprotein hemoglobin, which carries oxygen in the blood, changes shape when it binds oxygen. When it changes shape, it absorbs different wavelengths of light, making it change color. When blood is exposed to air, much more of the hemoglobin absorbs oxygen than had in the vein the blood came from (in the veins, the hemoglobin has already given up most of its oxygen to the body). Therefor, the blood turns red.

Answer 2

A major component of blood is the red corpuscles: an independent single cell that floats free in the blood plasma.

A major chemical component of a red corpuscles is hemoglobin: a protein.

A minor component of Hemoglobin is Iron in a +4 oxidation state.

Iron has two empty orbitals: places where electrons could go if there was sufficient nuclear charge to attract them.

Oxygen has two filled orbitals which it could use to form a chemical bond if there was an electromotive potential driving them to do so.

Unfortunately for these orbitals the electrostatics of both molecules are already balanced and there is no GREAT drive for a bond (ionic or covalent) to form. However, the electron configuration is still attractive and the two atoms would like to form a bond simply because of that. So what they do is they form a sticky sort of bond, what we call a hydrogen bond (when there is hydrogen involved) or London Forces (when hydrogen is not involved). This is what makes hemoglobin an oxygen carrying compound - it doesn't form a rigid bond with oxygen just a soft one that can easily be broken when more vigorous reactions demand the oxygen from it.

Now when any sort of bond is formed the valance electrons of the entire molecule get 'hybridized'. No valance electron is an island, they are all involved in the whole of the new molecular scheme.

Now an electron orbital has a number of energy states and in going from a low energy state to a high energy state the electron can absorb the discrete energy that is associated with that transition. This energy can be in the form of light, and as light has discrete energy states, only those photons with the energy that matches the transitional energy of the electron get absorbed.

Therefore when oxygen changes the electron configuration of hemoglobin, the now-altered hemoglobin absorbs different frequencies of light then what it did before. And, as it is the different frequencies of light that are reflected and absorbed that determine a substance's colour, the colour of hemoglobin changes.

It has always been fascinating to me how the addition or deletion of a single hydrogen atom to an extremely large and complex compound can effect a radical change in colour. In the case of Hemoglobin the addition is not even a real addition but only a temporary London bond.

Answer 3

Because your inside blood is purple and it doesnt have enough air for it to be red so when it comes out the blood just gets air real fast and it turns red real fast.

Answer 4

Yes, because your blood is really blue in the inside. When it comes out, oxygen hits your blood and it turns red.

Answer 5

It is not blue in the body. It is only a myth.

Answer 6

When your body temperature increases, your blood vessels near the skin dilate to release more heat. This dilation will cause your skin to turn red when you're hot.