MIXTURE TERMS
mixture - two or more substances associated and in contact with each other, found in
the same solid or container, but not chemically combined. They may or may not be well
dispersed.
miscible - liquids which are soluble(dissolve) in each other.
homogeneous mixture - Uniform in composition. Every portion exactly like any other
portion. Components are NOT readily distinguished by the unaided eye.
heterogeneous mixture - NOT Uniform in composition. Every portion NOT exactly like
any other portion. Components ARE readily distinguished by the unaided eye.
solution - homogeneous mixture of a solute dispersed in a solvent. Particles of solute
are 0.1 millimicron or smaller(1 micron = 1 millionth of a millimeter) The combination is
perfectly transparent. Particles will NOT settle out or separate. Solute particles will
pass through filter paper, animal membranes. Particles are NOT visible through any
type of microscope. Most common solutions involve water (solvent) and solids(solute)
Quick key - transparent
solvent - substance in which another material is dissolved to produce a solution. In a
solution, solvent is the largest by amount. Commonly, most solvents are liquids. Water
is the most common liquid used as a solvent.
solute - substance which is dissolved in a solvent to produce a solution. In a solution,
solute is generally the smaller in amount. Commonly, most solutes are(but not limited
to)solids. As it dissolves, solid solutes disappears from view. If solute is colored, color
eventually disperses uniformly as the solid disappears.
suspension - particles larger than 1 millimicron dispersed in a medium. Most typically
a solid dispersed in a liquid. The combination is visually cloudy ranging from hazily
opaque(Mountain Dew) to completely opaque(milk like). If the particles are from a solid,
they will settle out. If a liquid, then there will be
layers. The speed of settling/layering depends on the amount of particles, size of the
particles, temperature, and density or viscosity of the dispersing medium. Solid
particles can be filtered/centrifuged out, and are visible with the naked eye or simple
magnifyers. Quick key - will separate.
emulsion - specific mixture involving 2 liquids. The liquids are NOT miscible normally.
They are forced to be suspended in one another usually by the use of an emulsifying
agent. If left for an extremely long time, possible separation may begin, but is rare.
Typically, not transparent.
Quick key - two liquids that normally are NOT miscible.
emulsifying agent - colloidal particles which attach to liquid particles of immiscible
liquids. This causes the particles of both liquids to remain in suspension, unless
emulsifying agent’s attachment to the liquids is broken.
colloid - particles of a substance between 1 and 500 millimicrons dispersed in a
medium. The combination is transparent, particles will not settle or centrifuge out.
Particles will pass through filter paper, but not animal membranes.