The law stating that all spontaneous processes lead to an increase in the entropy of the universe.
Semimetal
See Metalloid.
Semipermeable
A quality of a membrane allowing only some components of a solution, usually including the
solvent, to pass through, while limiting the passage of other species.
Sigma (σ) bond
A bond formed by head-to-head overlap of orbitals from separate atoms.
Solid
The phase of matter possessing the greatest order, in which molecules are fixed in a rigid structure.
Solubility
A measure of the amount of solute that can be dissolved in a solvent at a certain temperature.
Solubility product (Ksp)
The equilibrium constant for the ionization reaction of a slightly soluble electrolyte.
Solute
The component of a solution that is present in lesser amount than the solvent.
Solution
A homogeneous mixture of two or more substances.
Solvation