Definition

1. Noun:
   • (Chemistry): A property of atoms or radicals; their combining power given in terms of the number of hydrogen atoms (or the equivalent) they can displace or combine with. It indicates the number of chemical bonds an atom can form.
   • (Biology): A relative capacity to unite or react or interact, as with antigens or a biological substrate. It describes the binding strength or affinity.

Usage Examples

• Noun (Chemistry):
  • Oxygen has a valence of two, meaning it typically forms two bonds.
  • The chemist calculated the valence of the metal ion in the compound.
• Noun (Biology):
  • The valence of the antibody determines its effectiveness in binding to the antigen.
  • Researchers studied the valence of the protein's interaction with the cell surface.

Advanced Usage

• "High valence": Refers to an atom or molecule with a strong combining power or high binding capacity.
  • A high valence state allows the element to form many different compounds.
• "Valence electron": An electron in the outermost shell of an atom that can participate in forming chemical bonds. (Note: This is a related compound term, not the target word itself).
  • The number of valence electrons largely determines an element's chemical properties.

Variants and Related Words

• Valency (n): An alternative term for valence, especially common in British English.
  • The valency of nitrogen in ammonia is three.
• Valent (adj): A combining form used to indicate a specific valence, as in "monovalent" or "trivalent."
  • A trivalent vaccine protects against three strains of the virus.
• Valence shell (n): The outermost electron shell of an atom. (Compound term).
  • Electrons in the valence shell are involved in bonding.

Synonyms

• Combining power (n): (Chemistry) The capacity of an atom to combine with others.
• Binding affinity (n): (Biology) The strength of interaction between molecules.

Related Phrases

• "Variable valence": The property of some elements to exhibit different valences in different compounds.
  • Transition metals like iron are known for their variable valence.
• "Zero valence": A state where an atom has no combining power, typically when its outer electron shell is full.
  • Noble gases like argon have zero valence under normal conditions.

Noun

1. (chemistry) a property of atoms or radicals; their combining power given in terms of the number of hydrogen atoms (or the equivalent)
2. (biology) a relative capacity to unite or react or interact as with antigens or a biological substrate