Реферат: The Comparative Abundance Of The Elements Essay

are carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur (known as CHONPS).

Most compounds in living matter are radically complex, each molecule could

contain hundreds or thousand’s of atoms. Carbohydrates and fats are compounds

which contain carbon, hydrogen and oxygen only. Proteins are also compounds and

they contain nitrogen, sulfur and occasionally phosphorus. Living matter cannot

live on these six elements alone; even though they make up 99% of the mass, they

also need some compounds of other elements such as calcium, potassium, sodium,

magnesium, iron, zinc, fluorine and others. These elements are required as

compounds so that livings things can use them.

3. The Universe

The universe is dominated by the elements hydrogen 83%, and helium 16%.

Other elements in the universe are oxygen 0.1%, carbon 0.03%, nitrogen 0.01%,

silicon magnesium and neon are all about 0.003% of the elements in the universe.

The abundance of hydrogen and helium in this cosmic distribution of the elements,

proves all the elements were formed by nuclear fusion in the stars, for example

the Sun. Hydrogen is a basic material for which the other elements are gradually

built.