Mixtures

Mixtures

á             two or more substances mixed together that are not chemically combined

 

Types of Mixtures

á             heterogeneous mixtures:

o           particles not dissolved

o           not the same throughout, such as gravel and water

á             homogeneous mixtures:

o           particles physically dissolved

o           same throughout, such as salt and water

 

Types of Heterogeneous Mixture

á             suspensions

o           solid suspended in a liquid

o           particles settle out

o           such as paint

á             colloids

o           homogeneously mixed but not dissolved

o           particles do not settle out

o           such as milk, whipped cream, toothpaste, and lotion

 

Types of Homogeneous Mixture

á             Solutions

o           solids dissolved in liquids

o           such as saltwater

á             Alloys

o           solids dissolved in solids

o           such as bronze

 

Table salt

á             chemical name: sodium chloride

á             chemical symbol: NaCl

á             an essential dietary substance

á             the main salt in seawater

á              forms cubic crystals when it crystallizes from evaporation

 

Crystals

á             the solid form of a material

á             can be identified by its repeating pattern or special shape

á             Examples are salt crystals, quartz crystals, and ice crystals (snowflakes).

 

Diatomaceous earth

á             the skeletal remains of diatoms, aquatic organisms (protists) with hard shells made of silica

á             mined from sedimentary deposits, ground to a fine powder, and used for filters (swimming pools), abrasives, and polishes

á             inert (not active) but can cause irritation if it gets into the eyes and nose