Transcript Matter Change

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Anything that has mass & take up space
Mass = measurement of the amount of matter an
object contains
Chemistry = the study of matter & the changes
that it undergoes
 Quantitative – numerical information
how much
how little
how big
how small
 Qualitative – descriptive information
condition, color, size, shape, odor, texture
Let’s Play
Physical Properties –
a characteristic that can be observed or
measured w/out changing the
identity of a substance
ex. color, odor, taste, hardness, density,
melting/boiling points,
state of matter
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States of Matter – the physical forms in
which all matter
exists on Earth
Solid
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def. shape
& volume
shape
independent
of container
particles are
packed
together
Liquid
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def. volume
shape depends
on container
particles can
move freely
Gas
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indefinite volume &
shape
particles move quickly
& spread apart
Physical Changes – a change that occurs in
the physical appearance of a substance, but
does not change its identity
Ex. melting, boiling, freezing, evaporating,
dissolving, condensing
breaking, splitting, grinding,
cutting, crushing
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COLOR
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STATE OF MATTER AT GIVEN TEMPERATURE
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MELTING POINT
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BOILING POINT
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DENSITY
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SOLUBILITY
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ELECTRICAL CONDUCTIVITY
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MALLEABILITY
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DUCTILITY
How easily can it be drawn into a wire?
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VISCOSITY
How susceptible is a liquid to flow?
SOLID , LIGUID, GAS
(mass per unit volume)
Does it conduct or is it an insulator?
How easily can it be deformed?
4. Chemical Properties – relates to a
substances ability to undergo changes that
transform it into a different substance
 easiest to see when a chemical is reacting
Chemical changes – a change that produces
matter with a different composition than the
original matter
ex. burning, rotting, rusting,
reacting, cooking, digestion,
respiration
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BURN
ROT
RUST
DECOMPOSE
FERMENT
EXPLODE
CORRODE
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EVOLUTION OF A GAS
FORMATION OF PRECIPITATE
(two clear solutions
when combined form solid)
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RELEASE
OF ABSORPTION OF ENERGY
COLOR CHANGE
Let’s Play
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A combination of 2 or more types of matter
Each component keeps its own identity &
properties
Components are only physically mixed & can
be separated using physical means
Heterogeneous mixture
a mixture in which the substances
are not evenly distributed
Homogeneous mixture –
a mixture or ‘solution’ in which the
substances are evenly distributed
Phase – used to describe any part of a sample
with uniform composition & properties
Homogeneous mixture
Heterogeneous mixture
1 phase
2 phases
 ‘Plays’ on differences in physical properties
1. Filtration – a technique that uses a porous barrier
to separate a solid from a liquid
Can you think of any
common applications?
2. Distillation – a technique that can be
used to physically separate most
homogeneous mixtures based on
differences in the boiling points of the
substances involved
3. Chromatography – a technique that is
used to physically separate the
components of a mixture based on the
tendency of each component to travel or
be drawn across the surface of another
material
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Every sample has same:
◦ characteristic properties
◦ composition
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Are made of:
◦ one type of atom: element
 Ex: iron, gold, oxygen
◦ 2 or more types of atoms: compound
 Ex: salt, sugar, water
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Simplest form of matter that has its own
unique set of properties
Can not be separated into simpler
substances by physical or chemical means
Each element is made up of a single type of
atom
ex. hydrogen, nitrogen, lead
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A substance that contains 2 or more
elements chemically combined in a fixed
proportion
Properties are different than the individual
elements
ex. Glucose (sugar)
Glucose – sweet, white solid
Carbon – black, tasteless solid
Oxygen – colorless, tasteless gas
Hydrogen – colorless, tasteless gas
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Physical methods do not work
 Recall…
Chemical changes – a change that produces
matter with a different composition than
the original matter
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Chemical Symbol
each element is represented by a oneor two-letter symbol
H
K
Au
H2O
C6H12O6
Hydrogen
Potassium
Gold
Water
Glucose
Trends:
1st letter = always capitalized
2nd letter = always lowercase
Subscripts = indicate the relative proportions of the elements
in a compound
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The process by which the atoms of one or
more substances are rearranged to form
different substances
Occurrence can be indicated by changes in
temperature, color, odor, & physical state
Also known as a chemical change
Chemical properties can only be observed
when a substance undergoes a chemical
change
The process of photosynthesis is a chemical
reaction in which light energy, carbon
dioxide and water, are transformed to
create glucose and oxygen.
The photosynthetic chemical reaction can be
shown by writing out the element symbols for
each compound.
Reactants
Products
substances to the left of the
arrow
 ‘ingredients’
 CO2 and H2O
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substances to the right of
the arrow
 ‘what is made’ or produced
 C6H12O6 and O2
 How can you tell whether a chemical change
has taken place?
1. Transfer of energy
Energy may be given off
in the form of heat or light
2. Change in color
Substances may
‘brown’
Indicators
3. Precipitate
A solid that settles
out of a liquid mixture
4. Gas production
Indicated by the
formation
of ‘gas bubbles’
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During any chemical reaction, the mass of
the products is always equal to the mass of
the reactants
+ O2
+ CO2 + H2O vapor
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Conservation of mass also applies to physical
changes…
10g of ice
10g of liquid H2O
Law of Conservation of Mass
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In any physical or chemical change, mass is
conserved
i.e. Mass is neither created or destroyed