Elementary Substances: A Fundamental Concept in Chemistry

Elementary substances are pure substances composed of only one type of element. They cannot be broken down into simpler substances. Examples include oxygen (O₂), phosphorus (P₄), iron (Fe), and silver (Ag).

Key Concepts

•  Elementary Substance vs. Element:

•  An element is a general term for atoms with the same number of protons (nuclear charge).

•  An elementary substance is an element in its free state. For instance, carbon can exist as diamond, graphite, or amorphous carbon, all of which are elementary substances of carbon.

Classification

Elementary substances are categorized based on their properties into:

•  Metals: Examples include iron (Fe) and silver (Ag).

•  Nonmetals: Examples include oxygen (O₂) and phosphorus (P₄).

Understanding these distinctions is crucial for grasping the basics of chemistry and the behavior of different substances.