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 makes up about 8% of the Earth's crust by weight, making it the third most abundant element in the Earth's crust after oxygen and silicon.
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