they are substances that require people to take chemical measures to separates them. in other words, you cant just separate them with a strainer or something of that sort.
Examples: H2O- water
NaCl- Table Salt
pure substance, propanone
The 2 categories are 'pure substances' or 'mixtures'
Pure substance
it is a pure substance.... not
Methane is a pure substance.
pure substance
pure substance
Pure Substance
A pure substance is classified by having a definite and constant composition. The substance can be either an element or a compound, but what makes the substance pure, is that it does not vary.
Neon is a pure substance. Elements and compounds are pure substances; mixtures are not.
CH3COOH is a pure substance. It is the chemical formula for acetic acid.
Refined substance can be a pure substance depending on the type of sugar used. If the refined sugar is white, then it is a pure substance. If it the refined sugar is brown, then it is not a pure substance.