substanceschemicals

Substanceschemicals refers to the concept that combines chemical substances and chemicals. In science, a chemical substance is a form of matter with a definite composition and set of properties. It can be a pure element, such as oxygen (O2), or a compound, such as water (H2O). Substances differ from mixtures, which have variable composition and may separate into components.

In common usage, chemicals are substances used in science and industry; the term is also applied loosely to any material with potential chemical properties, including household products and fuels.

Nomenclature and identification: chemical substances are named using conventions such as IUPAC naming, and are often recorded with identifiers like CAS Registry Numbers; descriptions may include molecular formulas, structures, and identifiers.

Properties: substances have physical properties (melting point, boiling point, density), chemical properties (reactivity, acidity or basicity), and distinct phases at given conditions.

Applications: chemical substances underpin research, manufacturing, environmental analysis, and regulatory compliance.

Safety and regulation: safety data sheets (SDS), the Globally Harmonized System (GHS) of classification and labeling, and regulatory frameworks such as REACH aim to communicate hazards and safe handling.

This entry notes that "substanceschemicals" is not a standard term in professional use, but serves to discuss the core idea of chemical substances and their properties, classifications, and regulatory contexts.