21% of air is pure oxygen
Phosphorus
Iron found as part of hemoglobin which comprises most of each red blood cell (RBC).
There is less than 2%. Most is found bound to hemoglobin.
Oxygen is the most abundant element in Earth's crust, making up about 47% of its mass. Silicon is the second most abundant element, comprising approximately 28% of the crust's mass.
The most abundant compounds in Earth's atmosphere are nitrogen and oxygen. Nitrogen makes up about 78% of the atmosphere, while oxygen comprises about 21%. Water vapor concentrations vary, but are typically around 1-4% of the atmosphere.
is the element with atomic number 8 and represented by the symbol O.Because it comprises most of the mass in water, oxygen comprises most of the mass of living organisms (for example, about two-thirds of the human body's mass)Oxygen is a member of the chalcoqen groupof the periodic table.
As mass percentage oxygen is the most abundant.
Phosphorus
Oxygen comprises about 21% of fresh air. Room air is nearly always refreshed from outsides sources sufficiently fast for this value to hold true. However, if ventilation is extremely poor it can differ.
Aluminum comprises 8% of the crustal elements.
Most of our body is made up of water (H20); therefore hydrogen is the most abundant (i.e. numerous) element and oxygen is the second most abundant. However, since oxygen is much heavier than hydrogen, it comprises a larger percentage of body weight (about 65%) than does hydrogen (about 10%).
Iron found as part of hemoglobin which comprises most of each red blood cell (RBC).
The most accurate fraction for the amount of oxygen in Earth's atmosphere is about 1/5. Oxygen makes up about 21% of the Earth's atmosphere.
The three most common gases in Earth's atmosphere are nitrogen (N2), oxygen (O2), and argon (Ar). Nitrogen makes up about 78% of the atmosphere, oxygen comprises about 21%, and argon is present at about 0.93%.
There is less than 2%. Most is found bound to hemoglobin.
Nitrogen and oxygen are the two most abundant gases in Earth's atmosphere, making up approximately 99% of its composition. Nitrogen comprises about 78% of the atmosphere, while oxygen makes up around 21%.
oxygen