The Vocabulary of
Chemistry
•refers to the lungs
 Pneuomono –
•above, beyond
 Ultra –
•small
 Micro –
•view
 Scop –
Lung Disease with•the
welts
resembling
element
silicon volcanoes,
 Silic –
 caused
Volcan – by the inhalation
•volcano, of
fireextremely small
 Coni –
particles•dust
of silicaceous dust
 Osis –
•disease or condition.
What does it mean?
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Chemistry is the study of matter. Matter has volume and mass.
Matter is described by its properties, which can be either chemical
or physical.
Chemical properties are properties that can be observed only
when substances interact with one another.
Reactivity with acid or Burning in the presence of oxygen, for
example, is a chemical property.
All chemical properties are intensive, which means they do not
depend on the amount of matter present.
For example, statues made of marble react with acid regardless of
the size of the statue. A small piece of chalk (calcium carbonate)
and a huge piece of chalk will both react with acid.
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Physical properties are properties that can be observed or
measured without changing the composition of matter.
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Examples of physical properties are
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color, texture, shape, length, and mass.
Some physical properties are intensive (which means they do not
depend on the amount of matter present).
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Intensive physical properties include melting point, color, density, and
texture.
 For example, a blue piece of paper will be blue no matter how big or small it
is.
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Some physical properties are extensive, which means they do
depend on the amount of matter present.
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Extensive physical properties include mass, volume, and length.
 For example, the length of a piece of wood depends on how big (or small)
the piece of wood is.
Properties are characteristics that you can use to describe or identify different
substances. (How things look, feel, taste etc.)
•State
•solid, liquid or gas
•Color
•color or colorless
•Texture
•if solid, smooth or rough
•Luster
•if it is a solid, shiny or dull
•Crystal structure
•Does the solid form crystals?
•What is the shape of the crystals?
•Odor
•How the substance smells.
• strong, weak, pungent, sweet, choking
•Solubility
•How much dissolves in water?
•How much dissolves in other solvents?
•Freezing or melting point
•At what temperature does the liquid turn into a solid or the solid into a liquid?
•Boiling point
•At what temperature does the liquid bubble and turn very rapidly into a gas?
•Density
•Mass of a specific volume of a substance
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Matter is changed by energy.
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Energy is the capacity to move or change matter.
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Forms of energy:
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potential energy – this is stored energy that is require to keep
and object in place.
 Elevated objects have more potential energy. A car parked on a
high mountaintop has more potential energy than a car parked in
the parking lot at NAI.
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Kinetic energy – this energy is due to motion. Only moving
objects have this type of energy.
The law of conservation of energy states that energy
cannot be created or destroyed; it may be transformed
or transferred from one object to another, but the total
amount of energy in the universe never changes.
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Physical changes are changes that only affect physical
properties; they are changes in form or shape.
With physical changes, you get back what you started
with, there is no change in a material’s chemical
identity or properties.
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Examples of physical changes:
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dissolving (including all phase changes)
boiling
tearing
pulling
malleability (able to be pounded into a sheet)
ductility (able to be made into a wire)
sectility (able to be cut with a knife)
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Chemical changes are changes that produce
one or more new substances.
With chemical changes, you cannot get back
what you started with… Chemical properties
have been changed.
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Examples of chemical changes:
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all chemical reactions
burning
digestion
fermentation
heat is produced
light is produced
a precipitate (a solid) is
produced
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Turns cloudy
new product (usually
indicated by a color
change)
a gas is produced
(evolved)
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Endothermic changes are physical or chemical
changes in which energy is absorbed.
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It will feel cool to the touch.
 For example, when ice melts, heat is absorbed; therefore,
endothermic change occurs.
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Exothermic changes are physical or chemical
changes in which energy is released.
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It will feel hot to the touch.
 For example, when a gas cools and becomes a liquid, heat is
released; therefore, exothermic change occurs.
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Matter contains phases.
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Phases are colors, shapes, and states of
matter.
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For example, a green and white pen has two
phases (“the white phase” and “the green
phase”).
Phases are separated by interfaces.
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A phase is any part of a system that has
uniform composition and properties.
For example, with the green and white pen,
the line where the green meets the white
would be called the “green-white” interface.
Matter can be classified as homogeneous
or heterogeneous.
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Matter that has only one phase is homogeneous.
Homogeneous matter made up of the same composition (definite
formula) is called a pure substance.
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Pure substances are either elements or compounds.
Elements consist of only one type of atom, and cannot be
decomposed into simpler substances by ordinary chemical means.
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Allotropes are multiple forms of one element.
 Examples of carbon allotropes are graphite, diamonds, and buckyballs.
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Compounds consist of more than
one type of atom chemically
combined that can be decomposed
into simpler substances (elements)
by ordinary chemical means.
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Organic compounds contain carbon
and hydrogen. Sugar (C12H22O11) is an
example of an organic compound. It
contains carbon (capital “C” with no
lower case letters next to it).
Inorganic compounds do not contain
carbon and hydrogen. Table salt
(NaCl) is an example of an inorganic
compound.
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Matter that has more than one phase is heterogeneous.
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Most things are heterogeneous.
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Examples of heterogeneous things are oil/water, concrete, and
granite.
A mixture is a collection of two or more substances
physically mixed together, not chemically combined,
that retain their identifying properties.
A heterogeneous mixture is a mixture containing
substances that are not evenly distributed.
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There are physically distinct parts each with different
properties.
 Examples include oil/vinegar salad dressing and frustration bottles.
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A homogeneous mixture is a mixture
containing substances that are uniformly
distributed (same composition throughout
with uniform properties).
Homogeneous mixtures can either be
solutions or colloids.
Homogeneous mixtures are composed of a
solvent and a solute.
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A solvent does the dissolving. In a
homogeneous mixture there is more solvent
than there is solute.
 For example, in a saltwater mixture, the water
is the solvent.
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A solute dissolves. In a homogeneous
mixture there is less solute than there is
solvent.
 For example, in a saltwater mixture, the salt is
the solute.
States of matter in
solution
Example
gas in gas
air (N2, O2 , Ar, CO2 , other gases)
gas in liquid
soda pop (CO2 in water)
liquid in liquid
gasoline (a mixture of
hydrocarbon compounds)
solid in liquid
sea water (NaCl and other salts in
water)
gas in solid
H2 in platinum or palladium
liquid in solid
dental amalgams (mercury in
silver)
solid in solid
alloys ( brass, (Cu/Zn), solder
(Sn/Pb)
•The main difference between a solution and a colloid is particle size.
•Solutions are mixtures with particle sizes at the molecule or ion level.
•The particles have dimensions between 0.1 to 2 nanometers.
•Colloids are mixtures with particle sizes that consist of clumps of
molecules.
•The particles have dimensions between 2 to 1000 nanometers.
• Typically solutions:
• are transparent; You can see through them.
•The mixture remains stable and does not separate after standing for any
period of time.
•The particles are so small they cannot be separated by normal filtration.
•Light can usually pass through the solution.
•If the solute is able to absorb visible light then the solution will have
a color.
•A blue liquid transmits blue light and absorbs the other colors of the
spectrum.
•The colloid looks homogeneous to the naked eye.
•Fog and milk are examples of colloids.
•Colloids frequently appear "murky" or "opaque".
•The particles are large enough to scatter light.
•You have experience with the way fog interacts with the
light from car headlights.
•Colloids generally do not separate on standing. They are not
separated by filtration.
More Dispersions
Liquids, solids, and gases all may be mixed to form
colloidal dispersions.
•Aerosols: solid or liquid particles in a gas.
•Examples: Smoke is a solid in a gas. Fog is a
liquid in a gas.
•Sols: solid particles in a liquid.
•Example: Milk of Magnesia is a sol with solid
magnesium hydroxide in water.
•Emulsions: liquid particles in liquid.
•Example: Mayonnaise is oil in water.
•Gels: liquids in solid.
•Mostly liquid, but behave like solids
•Examples: gelatin is water and protein.
•Suspensions are mixtures with particles that have diameters
greater than 1000 nm, 0.000001 meter.
•The size of the particles is great enough so they are visible to
the naked eye.
•Blood and aerosol sprays are examples of suspensions.
•Suspensions are "murky" or "opaque".
•They do not transmit light.
•Suspensions separate on standing.
•Components of a suspension can be evenly distributed by a
mechanical means, like by shaking the contents, but the
components will settle out.
•The mixture of particles can be separated by filtration.
•You can tell suspensions from colloids and solutions
because the components of suspensions will
eventually separate.
•Colloids can be distinguished from solutions using the
Tyndall effect.
•A beam of light passing through a true solution,
such as air, is not visible.
•Light passing through a colloidal dispersion, such
as smoky or foggy air, will be reflected by the
larger particles and the light beam will be visible.
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Mixtures can be separated according
to their properties by the following
methods:
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Filtration – separation by particle size
 example: coffee grounds and water
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Decanting
Centrifugation
Evaporation
Distillation – separating substances that
have different boiling points
Sublimation
Crystallization
Chromatography – used to separate the
components of a solution (can be used to
separate colors)
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Kuwait is a tiny country at the head of
the Persian Gulf. Although it has some
of the richest oil wells in the world, it
has virtually no fresh water. The
populations of Kuwait has grown
rapidly in recent years as people from
all over the world have flocked to this
desert kingdom to work in its oil fields.
To support the growing population,
Kuwait developed massive water
desalination plants. In these plants, sea
water from the Persian Gulf is heated
to boiling. Steam rises from the surface
of the water, leaving salts and
pollutants behind. The steam is then
cooled and condensed to pure liquid
water that can be used for drinking,
irrigation, or normal household uses.
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Why do you
think
desalination is
rarely
employed to
provide water
for agriculture?
How can the
rate of
distillation be
increased?
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In 1849 many adventurers
came to California in search of
gold.
Some of the gold-seekers
decided to avoid the Sierra
Nevada Mountains by
venturing south through a
large desert basin in
southeastern California.
Unfortunately, many died of
dehydration as they crossed
the hot dry valley. The region
became known as Death
Valley, and is now a National
Park.
Explain how this apparatus would
work.
What would be ideal conditions (i.e
soil and temperature) for this method
of water collection to work?
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Properties to look at
in order to decide
separation
technique:
Density
 Volatility
 Solubility
 Reactivity
 Magnetism
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Mixture
Element
Compound