Transcript SEPARATION OF MATTER - Los Angeles City College

SEPARATION OF MATTER
• Matter is separated into
three states: SOLID,
THE ATOMIC - LIQUID, & GAS.
MOLECULAR
THEORY OF • Matter can also be broken
down into distinct
MATTER
materials, each category
representing a specific type
of material. A flow chart
will show the linking of
these types of materials.
The Atomic-Molecular Theory of Matter
• Physical properties: characteristics of a material which
may be determined without altering the composition of the
material; bp (boiling point), mp, color, density etc., no
change in the chemical identity occurs.
• Chemical properties: characteristics of a material which
involves altering the composition of the material, the ability
to form new substances by decomposition or reactions
with other substances. A rearrangement of the atoms.
• Phase: a sample of matter that is uniform throughout,
both in its chemical composition and its physical state.
• Chemical Bonds: the attractive forces, “ the glue”, strong
enough to maintain a group of atoms together for an
indefinite amount of time.
Physical Changes:
The substance or mixture does not alter in atomic
composition. Some Physical Changes are boiling,
evaporation, condensation, freezing, melting,
sublimation, and deposition.
Associated with Physical Changes are Physical
Properties like boiling or freezing point, density,
hardness, and state of matter.
H2O (l)  H2O (g)
Chemical Changes:
The substance changes in its atomic composition, the
atoms are rearranged and new substances are formed.
2 H2O (l)  2 H2 (g) + O2 (g)
The Atomic-Molecular Theory of Matter
THE MOLECULAR THEORY OF MATTER
Separated by physical
methods
MATTER
HOMOGENEOUS
MIXTURE
(Solution)
HETEROGENEOUS
MIXTURE
Separated by physical methods
PURE
SUBSTANCE
COMPOUNDS
ELEMENTS
Separated by chemical methods
Separated by physical
methods
The Atomic-Molecular Theory of Matter
*definitions*
• Matter : occupies space and has weight.
• Energy : the ability to do work
• Materials: a particular type of matter, generic term.
• Mixture: has variable composition, can be separated by
physical methods.
• Heterogeneous mixture: has properties which vary from
region to region, can be separated into a homogeneous
mixture or a substance.
• Homogeneous mixture: uniform properties throughout,
also called a solution. Can be separated into
substances.
The Atomic-Molecular Theory of Matter
• (Pure) substance: a material which can not be separated
by physical methods into 2 or more materials which have
different characteristics.
• Compounds: a material containing two or more elements or
molecules.
• Molecules: the smallest grouping which a substance can be
divided into without forming a new substance, a group of 2 or
more atoms held together by strong forces called "bonds".
• Atoms: the smallest particle of matter which has distinctive
chemical characteristics, generic term, composed of a nucleus
surrounded by electrons.
• Elements: a specific substance which can not be decomposed
into simpler substances by chemical means, an atom with a
specific number of protons, neutrons, and electrons.
The Atomic-Molecular Theory of Matter
A “microscopic” view
The Atomic-Molecular Theory of Matter
THE ATOMIC THEORY OF MATTER
ATOMS
ELEMENTS
NUCLEUS
ELECTRONS
(negative particle)
-
PROTONS
NEUTRONS
(positive particles)
(neutral particles)
+
The Atomic-Molecular Theory of Matter
• Nucleus: the small positively charged kernel,
composed of protons and neutrons.
• Protons: a positively charged particle, has a mass =
1.67 x 10-27 kg or 1 amu (atomic mass unit) usually
symbolized as H+ or p+.
• Neutrons: neutral particles with the same mass as the
proton, contributes weight but no charge.
• Electrons: a negatively charged particle, has a mass
= 9.1 x 10-31 kg (1/1837 amu) usually symbolized as e-.
may come in one of three forms:
Periodic Table of the Elements
Alkali
H
Alkalin
e-earth
Inert
Chalogen
Representative Elements
Li Be
metalliod
Na Mg
Transition Metals
nonmetal
K Ca
Sc
Ti
V
Rb Sr
Y
Zr
Nb Mo Tc
Cs Ba
La - Lu
Hf
Ta
Fr Ra
Ac - Lr
Rf
Db Sg Bh Hs
W
Ni
C
N
O
F
Ne
Al
Si
P
S
Cl
Ar
Cu Zn Ga Ge As Se
Br
Kr
Ru Rh Pd Ag Cd
Re Os
Ir
Pt
He
B
metal
Cr Mn Fe Co
Halogen
Au Hg
Mt Uun Uuu Uub
In
Sn Sb Te
I
Xe
Tl
Pb
At
Rn
Bi
Po
THE PERIODIC TABLE
Metals
Nonmetals
• Located on the left side of
the periodic table
• Tends to lose electrons to
form cations
• Has low ionization energies
& electronegativity values
• Forms compounds with
nonmetals but not other
metals
• Good conduction of heat and
electricity
• Lustrous & malleable solids
excepts Hg which is a liquid
• Ductile
• Located on the right side of
the periodic table
• Tends to gain electrons to
form anions
• Has high ionization
energies &
electronegativity values
• Forms compounds with
both metals and nonmetals
• Poor conduction of heat
and electricity
• Non-lustrous & brittle or
gaseous
• Non-ductile
IONS
“a charged atom”
The number of protons do NOT equal the number of
electrons.
Cations:
positively charged ions formed when electrons are lost.
Na+
Anions:
negatively charged ions formed when electrons are gained.
Cl-
COMPOUNDS
MOLECULES
Composed of two or
more nonmetals
IONIC SALTS
Composed of a metal
& a nonmetal
MOLECULE
Ionic Salt
Reading Chemical Formulas
BaCO3
(NH4)3PO4
CuSO4•5H2O
CH3COOH
CuCO3•Cu(OH)2
•Chemical structure: the position and geometry of the atoms in a molecule.
ANALYSIS OF MATTER
MATTER
Is it uniform?
YES
NO
HOMOGENEOUS MIXTURE
HETEROGENEOUS MIXTURE
blood, soil
Can it be separated
by physical methods?
YES
NO
HOMOGENEOUS MIXTURE
saltwater, rubbing alcohol
PURE SUBSTANCE
Can it be decomposed into
simpler substances using
chemical methods?
YES
COMPOUND
water
NO
ELEMENT
carbon
PRACTICE PROBLEMS #4
1. Classify the following as an element, compound, or mixture
(heterogeneous or homogeneous).
E
HO
• _____ air
_____ oxygen
E
C
• _____
tin can
_____
sugar
HE
HO Windex
• _____
_____ crude
oil
HE
HO gummi bear
• _____
suntan lotion
_____
2. A white solid is dissolved in water. The resulting colorless, clear liquid
is boiled in a beaker until dryness. White crystals remain in the beaker.
Homogeneous mixture
The liquid can be classified as a(n) ______________.
3. Classify the following as physical or chemical changes.
CC
CC
• _____ photosynthesis
_____ baking
PC writing with pencil
PC
• _____
_____
snowing
GROUP STUDY PROBLEM #4
1. Classify the following as an element, compound, or mixture
(heterogeneous or homogeneous).
• _____ wine
_____ root beer
• _____ penny
_____ table salt
• _____ Bleach
_____ wood
• _____ diamond
_____ vinegar
2. A clear blue liquid in an open beaker was left in the hood. After 1 week,
the beaker contained only blue crystals. The original liquid can be
classified as a(n) ______________.
3. Classify the following as physical or chemical changes.
• _____ perspiration
_____ sugar dissolving
• _____ fermentation
_____ aging