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Incoming links: Chemistry 2e by Paul Flowers and others 11.1 The Dissolution Process
Solution (chemistry) Created 2026-10-13 Updated 2026-10-14
A chemical solution is a homogeneous mixture in which designated solutes are distributed in a solvent. Representative equal-volume samples have the same composition after mixing. Individual molecules and ions remain distinguishable. The solute/solvent labels describe their roles in this mixture.[ref]
A dissolved solute is dispersed as molecules, chemical atoms, or ions, rather than as the larger solid particles of a particle suspension. For example, sucrose retains its molecular formula during dissolution in water; a chemical reaction is not required. Dissolved sodium chloride supplies sodium cations and chloride anions, surrounded by water molecules through solvation. Dissolved does not mean chemically destroyed or converted into water.[ref]
11.1 The Dissolution Process. Chemistry 2e, §11.1, opening molecular and ionic examples and defining traits of solutions
Dissolution disperses particles while preserving their chemical elements
. Original schematic with invented particle positions, not a microscopy image. Top: four generic neutral molecules retain their identity. Bottom: four sodium cations and four chloride anions separate from an ionic crystal. Pale dots represent water molecules; sizes, spacing, and counts are explanatory, not measured. Solvation surrounds each dissolved species; the diagram does not specify a hydration shell geometry. Details.
This makes a useful connection between microscopic identity and laboratory sampling. If a chemical solution is well mixed, the amount of substance in a measured portion follows from its concentration and volume. A scoop from a poorly mixed particle suspension need not represent the whole vessel. Visual clarity alone cannot establish composition or exclude a fine dispersion; the quantitative claim needs representative sampling.
Solvation Created 2026-10-14 Updated 2026-10-14
Solvation is stabilization through interactions between a solute and its solvent. It involves both the solute's surroundings and reorganization of the solvent: neighbors move, orientations change, and existing interactions compete with new ones. Electric forces, Van der Waals forces, and specific interactions such as hydrogen bonds can contribute. Solvation can also occur at groups on an insoluble material, so it does not require complete dissolution.[ref]
Solvation by water is called hydration. Hydration of ions is the charged special case, but neutral molecules such as sucrose can also interact with water without becoming ions. A hydrated cation retains its positive net electric charge; orienting neutral water molecules around it does not supply an extra Electron. Dissolution, desolvation, and ionization describe different changes, as the examples below show.[ref][ref]
11.2 Electrolytes. Chemistry 2e by Paul Flowers and others; “Ionic Electrolytes” and “Covalent Electrolytes”
The useful question is therefore not just whether a solute attracts a solvent, but how much the whole system gains after paying for the rearrangements. Solvation free energy describes a specified transfer into a solvent; solvation thermodynamic balance explains why even cooling during dissolution can accompany favorable mixing. The existing solubility discussion concerns how much remains dissolved at chemical equilibrium.
Solvent Created 2026-10-13 Updated 2026-10-14
A solvent is the component designated as the medium of a chemical solution, commonly the component present in greatest proportion. Water is a common solvent, not a necessary one. A mixture of mostly ethanol with a little water can designate ethanol as solvent and water as solute. Chemical solutions can also be gas or solid mixtures; molecular nitrogen is the principal medium of ordinary well-mixed air. When proportions are comparable, state the convention explicitly.[ref]
The solvent is part of the final sample. Choosing it influences solubility and solvation; measuring its added volume alone does not determine the final chemical solution volume. Solvent and solute masses add in a closed account, whereas the final volume should be measured rather than inferred by adding pre-mixing volumes.