Electrical properties from 10−3 to 10+9 HZ−−Physics and chemistry

In dry materials, physical factors control all electrical properties. The addition of a polar liquid solvent such as water or alcohol adds a host of solvent‐rock chemical interactions. These chemical interactions range from oxidation‐reduction corrosion, cation exchange, and clay‐organic processes at frequencies below 1 Hz to diffusion‐limited relaxation around colloidal particles at frequencies up to 100 MHz. Most mixing formulas are based upon physical mixing of noninteracting materials, and they fail when chemical processes appear. If the specific chemical processes are identifiable, combined physical and chemical mixing formulas must be used. The simplest systems to model are noninteracting physical mixtures of solvents with pure silica sand. The most complicated systems are mixtures of solvents with chemically surface‐reactive materials like clays and zeolites.