Element - the simplest form of matter that can exist under normal

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Applied Chemistry
Mr. Gensits
Class Notes 9/27/2010
Properties of Matter
Describing Matter
Mass – a measure of the amount of matter an object contains
Volume – a measure of the space occupied by an object
Extensive Property – a property that depends on the amount
of matter in the sample
Intensive Property – a property that depends on the type of
matter, not the amount of matter
Identifying Substances
Substance – matter that has a uniform and definite
composition
Every sample of a given substance has identical intensive
properties because every sample has the same definite
composition!
Physical Property – a quality or condition of a substance that
can be observed or measured without changing the substance’s
composition.
Examples: hardness, color, mass, boiling point, solubility
in water, odor
States of Matter
1. Solid
Has a definite shape and volume
Cannot be easily compressed
Expands only slightly when heated
The particles are packed tightly together
Forces hold the particles in position
There is little movement of the particles
2. Liquid
Flows
Has a fixed volume but takes the shape of the container
Cannot be easily compressed
Less dense than solids
Expands slightly when heated
Particles are close to one another but are not held in position
Arrangement of particles is not rigid or orderly
3. Gas
Flows
Takes both the shape and volume of the container
Expands to fill whatever container it is in
Easily compressed
Particles are far from one another
Vapor - a substance that is in the gaseous state but is
normally a liquid or solid at room temperature
Examples: Water, Mercury, Gasoline
4. Plasma – an ionized gas in which the electrons have been
stripped from the individual atoms allowing the sample to act
as a whole.
This is the most common form of matter in the universe!
5. Bose-Einstein Condensate – a “superfluid” in which atoms
have collapsed into a single quantum state
All of the atoms are identical and it is impossible to tell them
apart.
Physical Changes – some properties of a material change, but
the composition of the material does not change
Examples: boiling, dissolving, cutting, freezing, crushing
All phase changes are physical changes!!
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