For common cast iron, the main elements of the chemical composition are carbon and silicon.
The search for life focuses mostly on planets with liquid water, a heat or energy source, and chemicals like carbon , hydrogen, and oxygen.
the level of carbon in the atmosphere has been consistently rising
Combustion, or burning, is a chemical process involving carbon , hydrogen and oxygen.
On the Earth, it is found only in combination with other elements, such as oxygen, carbon , and nitrogen.
a bike with a carbon frame
The ozone depleting compounds contain combinations of the elements chlorine, fluorine, bromine, carbon and hydrogen.
Silicon reacts chemically like carbon although it does not form multiple bonds.
The action of the micro-organisms will reduce the nitrogen, carbon and phosphate levels of the dam.
Consider the top five constituents of the cosmos, in order of their abundance: hydrogen, helium, oxygen, carbon , and nitrogen.