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Compostion of molecules
What is a molecule ?
gather to form molecules.
A molecule is a group of several identical or different atoms linked
A molecule is represented by a formula that indicates:
- The different kinds of atoms within the molecule (Each atom is
represented by its symbol)
- The number of each atom (with a subscript after the symbol)
For instance the water molecular formula is H2O:
- The symbol H indicates that the water molecule consists of
atoms of hydrogen and its subscript ( 2 ) indicates that there are two
- The symbol O indicates a water molecule is composed of oxygen atoms
but the absence of subscript indicates that there is only one atom.
The water molecule thus consists of two hydrogen atoms and one oxygen
Some examples of chemical
formulas to know:
The molecule of dioxygen: formula O2
dinitrogen molecule: formula N2
of carbon dioxide: formula CO2
molecule: formula CH4
The molecule of carbon monoxide: formula CO
The butane molecule: formula C4H10
Atoms are represented by models which are colored spheres.
can be used to build molecules
Some simple molecular models
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