valence electrons are the number of electrons in the outer shell. there can only be 8 electrons in the outer shell. The number of valence electrons can be used to determine how many bonds are needed.
For example: H2O
O (oxygen) has 6 valence electrons H (hydrogen) has 1 valence electron
O needs 2 more electrons to be stable H needs 1 more electron to be stable
O forms one bond with two H atoms to form H2O.
Valence electrons are the outermost electrons in an atom and are key to determining how atoms bond to form molecules. Atoms aim for stability by completing their valence shells, leading to covalent or ionic bonds depending on their electron configurations. The number of valence electrons allows us to predict the type of bonds an atom will form, shaping the structure of molecules.
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