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General Chemistry

Valence

Definition and meaning of Valence in chemistry.

Valence is the combining capacity of an element, typically determined by the number of electrons in its outermost shell. It represents how many bonds an atom can form with other atoms to achieve a stable electron configuration.

In more detail

The concept of valence explains why elements combine in specific ratios to form compounds. Atoms gain, lose, or share valence electrons to fulfill the octet rule, which states that a full outer shell of eight electrons is most stable. Elements in the same group of the periodic table usually exhibit similar valences because they have the same number of outermost electrons. Transition metals can often exhibit multiple valences depending on the reaction conditions and their electron configurations.

Key facts

FieldGeneral Chemistry
Determining FactorOutermost electrons
Carbon Valence4
Example

Carbon has a valence of four, meaning it can form four covalent bonds with other atoms, as seen in methane (CH4).

Frequently asked questions

Is valence the same as oxidation state?

No, valence is the number of bonds an atom forms, while oxidation state indicates the hypothetical charge an atom would have if all bonds were completely ionic.

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