Chem Matter Notes

Matter

Anything that has mass and takes up space

Types of matter

pure and mixtures

Pure substances

elements or compounds

Elements

One type of atom (single or diatomic)

Compounds

made out of molecules (2 or more atoms bonded together)

Molecules

Made out of bonded atoms

Atoms take on new identities+properties when bonded to atoms of other elements

Mixture

Homogeneous or Heterogeneous

Homogeneous and heterogeneous

substances retain identities in mixtures

Mixtures can be combinations of…

elements, compounds or both elements and compounds

Homogeneous

Uniform particles throughout

Heterogeneous

Particles not dispersed evenly

Diatomic elements

Elements that exist as pairs in nature (Hydrogen typically exists as H₂)

Particle diagrams 

lets us model things that are happening at microscopic and atomic level 

• elements, diatomic elements, compounds

• mixtures

• States of matter 

Physical properties of matter

characteristic observed without changing composition of substance (density, phase change, malleability)

Chemical properties

The ability of inability of a substance to combine with or change into one or more other substances

• seen when a new substance is formed

Physical properties can be…

intensive - independent of the amount of substance present (density, boiling point, melting point)

or

extensive - dependent of the amount of substance present (mass, volume, length)

Signs of chemical changes (5)

• color change

• production of gas

• formation of a precipitate

• temperature change

• production of an odor

Solution

type of homogeneous mixture where a substance is dissolved in a solvent

• separated using evaporation or distillation 

Filtration

separates solids from liquids and solutions

Distillation

Separates homogeneous mixture based on differences in boiling points

Evaporation

Separates homogeneous mixture by evaporating liquid component and leaving a crystallized solid component

Chromatography

Separates substances based on differences in solubility in a solvent