How can pure substances be described in everyday terms?

Pure substances are defined as materials that consist of only one type of particle and have consistent properties throughout. In everyday terms, describing a pure substance as one without any additives and in its natural state emphasizes its unaltered and homogenous nature. For example, pure water or pure gold is composed entirely of water molecules or gold atoms, respectively, with no other materials mixed in. This definition aligns with how people understand purity, as it indicates that the substance is in its most basic form, free from impurities or contaminants that would otherwise change its composition or characteristics. Additionally, the natural state descriptor reinforces the idea that the substance hasn't undergone chemical alterations that would introduce other components or compounds.