Structure 1.1 Introduction to the particulate nature of matter

Any substance that has mass and volume. Composed of atoms/ions/molecules/etc.

pure substance made out of atoms with the same number of protons, and cannot be chemically broken into a simpler substance

Pure substance composed of two or more atoms of different elements chemically bonded in a fixed ratio

Form of matter with consistent chemical composition, fixed properties and cannot be separated into simpler substances by physical means

More than one element or compound in no fixed ratio, which is not chemically bonded and can be separated by physical methods into pure substances (mixed but not chemically combined). Can have variable properties depending on composition

Mixture that does not have a uniform composition and properties throughout (e.g. rocky road)

mixture with a uniform composition and properties (e.g. steel, air, any aqueous solution)

reversible change in the physical properties of a substance in which no new substances are formed

solid/liquid/gas that dissolves in a liquid solvent to form a solution of solvated ions or molecules

A usually liquid substance that is capable of dissolving a solute

Liquid mixture in which the solute is uniformly distributed within the solvent i.e. homogenous

(of a solute) surrounded by the solvent’s molecules

ions solvated with water (surrounded by water molecules)

Containing no water/opposite of hydrated

Solvent: water Solute: sodium chloride Solution: aqeuous mixture of sodium and chloride ions solvated with water

dissolves readily in a solvent, particularly water

a solution where no more solute can dissolve at a particular temperature

amount of solute needed to form a saturated (maxed out) solution

Often expressed as the mass that will dissolve into 100cm3 at a particular temperature

when liquids mix together, they form one uniform layer of homogeneous mixture

when liquids mix together, they do not mix and instead form two separate layers

Filtration Evaporation Recrystallisation Distillation Paper chromatography

physical separation process that separates solid matter and fluid by the use of a filter medium that permits only the fluid to pass through

heterogeneous, insoluble solid + liquid