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Chemistry vocabulary · Chemical Bonding and Structure

Molecule

Meaning in chemistry, with examples

/ˈmɒlɪkjuːl/nounCore term

In chemistry, molecule means: A group of two or more atoms held together by covalent bonds. It is the smallest particle of a substance such as water or oxygen gas that still has that substance's chemical properties.

In Turkish: molekül

How it is used

Used whenever you describe covalent substances: the shape of a molecule, polar and nonpolar molecules, large molecules such as proteins. Ionic solids like NaCl are not usually called molecules; chemists speak of formula units instead.

Example sentences

  1. Carbon dioxide is a linear molecule, so its bond dipoles cancel out.

  2. One molecule of glucose contains six carbon atoms.

Common collocations

  • polar molecule
  • water molecule
  • small molecule
  • shape of a molecule
  • diatomic molecule
  • atomThe smallest unit of an element that keeps its chemical identity. It has a tiny nucleus of protons and neutrons, with electrons moving around it.
  • covalent bondA chemical bond in which two atoms share one or more pairs of electrons. It usually forms between nonmetal atoms, as in H₂, H₂O and CH₄.
  • compoundA substance made of two or more different elements chemically joined in a fixed ratio. Water (H₂O) and table salt (NaCl) are common examples.
  • polarDescribes a bond or molecule in which electrons are shared unevenly, so that one end is slightly negative and the other slightly positive. Water is a typical example.
  • Lewis structureA drawing of a molecule or ion that shows its atoms, the bonds between them as lines, and the lone pairs of valence electrons as dots.

More terms: Chemical Bonding and Structure

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