The protein 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). Therefore, the blood turns red.
Source(s):http://www.newton.dep.anl.gov/askasci/bi…Blood in the body is blue, when exposed to air it turns red.AnswerBlood may be thought of as a possible answer; however, blood is not actually blue. See related answer below.
Blood is actually red due to the presence of hemoglobin, a protein that contains iron and binds with oxygen. When blood is oxygen-rich, it appears bright red, while oxygen-poor blood appears darker red. The misconception that blood is blue comes from the color of veins, which can appear blue under the skin due to how light interacts with it.
blue litmus paper turns to red when its in contact with acid
When you mix red and violet it turns into a dark dark red like a blood color.
A red litmus paper turns blue in the presence of a base/alkali, while a blue litmus paper turns red in the presence of an acid.
Your blood turns red when it hits the air.
your blood is purple but turns red when it meets with oxygen
its blue/dark red blood before it turns fire engine red by oxygen not black.
Colloidal gold turns to red due to the red blood cells of the gold particles.
Blood is actually a bluish,purplish color. Whenever you see blood, it is red because once the blood touches the air, it turns red.
Blood can only be red! Bright red blood is usually of arterial origin and is oxygenated. Dark red blood is usually venous. They are both healthy. Be more specific. One thing for sure: there are no "blue blood people"
It turns red
Oxygen has hit the bood. Although the true color of blood is blue, when blood is exposed to oxygen it turns red.
That's easy. When blood is in your body it is blue that's why your veins are blue. When oxygen meets the blood the blood turns red.
Red blood cells contain hemoglobin.
blood is originally blue but when its exposed to oxygen it turns red
blood is red blood cells that help your body flush out the bad stuff. blood is blue when its inside you and when it mixes with oxegn it turns red.