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What happens when a molecule is divided into pieces smaller than a single molecule?

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representations of molecular structure — molecule Several methods of representing a molecule's structure. In Lewis structures, element symbols represent atoms, and dots represent electrons surrounding them. A pair of shared electrons (covalent bond) may also be shown as a single dash. The ball-and-stick model better illustrates the spatial arrangement of the atoms. For aromatic compounds, the Kekulé structure is common, in which each bond is represented by a dash, carbon atoms are implied where two or more lines meet, and hydrogen atoms are usually omitted. Bond-line formulas, similar to the Kekulé structure, are often used for complex nonaromatic organic compounds. Sugars are often drawn as Fischer projections, in which the carbon “backbone” is drawn as a straight vertical line, with carbon atoms implied where horizontal lines intersect the vertical one.

When a substance is divided into parts smaller than a single molecule, the chemical bonds that hold the constituent atoms together are broken.1

At this stage of fragmentation, the resulting pieces differ from the original substance in their composition and always differ in their chemical properties. This process is often referred to as dissociation, where a compound breaks into simpler constituents, such as ions, which are electrically charged particles. In the context of chemical reactions, these broken pieces or atoms are typically reassembled into new products by forming different chemical bonds.123