Section 2.2- Properties and Changes of Matter Flashcards
a descriptor
one type of matter my be described, identified, or distinguished form another by its
properties
properties that describe a substance’s appearance
color, odor, density, hardness, solubility, taste, state, boiling point, melting point
physical properties
properties that describe how matter reacts to change into other chemically different substances have different properties; these are called
changes the identity of a substance
chemical properties
changes in the physical appearance of matter that do not change the identity or chemical composition of a substance
physical changes
___________ changes may often be reversed by physical processes
physical
a change in which a substance becomes a different substance with a different composition and properties is a
chemical change
chemical changes can be reversed only by
other chemical changes
observation that can be made that will suggest a chemical change has occurred
- formation of gas
- formation of precipitate (an insoluble substance)
- liberation absorption of heat, light, or some other form of energy
- a distinct change in color
homogenous mixtures in liquid form may be separated by ______________ if the components have widely differing boiling points
distillation
as temperature of the mixture is raised, the more volatile component of the mixture boils first. The vapor produced may be collected, cooled, and condensed into the pure liquid, leaving the nonvolatile component behind. This is called
simple distillation
in mixtures of several liquids hacing boiling points that are close together, this process must be used
fractional distillation
a solid containing a relatively small amount of solid impurity may sometimes be purified by a technique called
fractional crystallization
complex mixtures can be separated by the technique
chromatography (color writing)
one of the simplest forms of chromatography
paper chromatography
more advanced forms of chromatography
column or gas
