Matter & Its Properties
MOD E RN CH E MI S TRY T E X T B OOK: CH . 1
Basic Building Blocks of
Matter
What is matter?
• Anything that takes up space and has mass
• Takes up space  volume
• Certain amount of stuff  mass
• How does one make stuff?
• Start with the ATOM!
What is chemistry?
• The study of matter and the changes it
undergoes
• Composition
• Structure
• Properties
• Energy changes
Elements vs. Compounds
• Atom – smallest unit of an element that has the
chemical identity of that element
• Element – Pure substance that cannot be broken
down into simpler, stable substances
• So only 1 kind of atom
• Examples; Na, H2, Cl2, Ca
• Compound – Pure substance that can be broken into
simpler, stable substances
• must have 2 different kinds of atoms
• Examples; H2O, NaCl, CO2
Is this an element?
States of Matter
• Elements & Compounds can be found in many
different states of matter or phases
What’s the Difference between States of Matter Video
• Substances only move from one phase to another by
physical means.
Physical vs. Chemical Properties
• Physical change – change in which identity
of substance is not altered
• Examples: ripping, heating, freezing
• Physical property – characteristic of a
substance that can be observed/measured
without altering substances identity
• Examples: color, size, texture
• Extensive Property:
a property of a substance that changes when the
amount changes; it is dependent on the AMOUNT
of substance present
• Examples: volume, mass, energy…
• Intensive Property:
a property of a substance that is always the same
for that substance; it is NOT dependent on the
AMOUNT of substance present
• Examples: density, boiling point, melting point,
conductivity…
• Physical changes will always require the
absorption/release of energy
• (Heat or light)
What physical characteristics can you observe
to determine a substance’s state of matter?
• Shape
• volume
Indefinite volume
Definite volume
Indefinite shape
Definite shape
Definite volume
Indefinite shape
• Plasma: high-temperature state of matter in which
atoms lose most of their electrons
What if a substance’s identity is altered?
Chemical Property – ability to undergo changes that
transforms substance into a new substance
Chemical change – change in which 1 or more
substances are converted into different substances
Chemical Changes
Reactants
substances that react
yields
Products
substances that are formed
Evidences of Chemical Change
Formation
of a gas
Formation of
precipitate
Evolution
of energy
(heat/light)
Color
change
• Energy is always involved in physical and in chemical
changes
• Law of Conservation of Energy: energy can be
absorbed or released, but is never destroyed or
created.
Physical
1. Color
Chemical
Extensive
✔
2. Combustibility
Intensive
✔
✔
✔
3. Hardness
✔
✔
4. Luster
✔
✔
5. Flammability
✔
✔
6. Reacts with acids to form
H2
✔
✔
7. Mass
8. Density
✔
✔
9. Melting Pt.
✔
✔
✔
✔
10. Can neutralize a base
11. Ductility
✔
12. Odor
✔
13. Weight
✔
14. Malleability
✔
✔
✔
✔
✔
✔
15. Tendency to corrode
16. Length
✔
✔
✔
✔
C
_______ 1 . Hydrochloric acid
reacts with potassium
hydroxide to produce a salt,
water and heat.
P 2. A pellet of sodium
_______
is sliced in two.
P 3. Water is heated
_______
and changed to steam.
C 4. Iron rusts.
_______
P 5. Evaporation
_______
C 6. Milk sours.
_______
P 7. Ice melting.
_______
C 8. Wood rotting.
_______
C 9. When placed in
_______
H2O, a sodium pellet
catches on fire as H2 gas is
liberated and sodium
hydroxide forms.
C 10. Grass growing in
_______
a lawn.
P 11. A tire is inflated
_______
with air.
C 12. Food is digested
_______
in the stomach.
P 13. Water is
_______
absorbed by a paper towel.
P 14. Sugar dissolved
_______
in water.
Classification of Matter
G ROUP I NG MAT T E R T O MAK E I DE NTIF I CATI ON E AS I E R
Mixtures
Blend of 2 or more kinds of matter, each that retain its
own identity and properties
• Mixed together physically
• Can be separated physically (no chemical rxn’s
needed)
• Homogeneous (solutions): uniform in composition
• Salt – water solution
• Heterogeneous: not uniform throughout
• Clay-water mixture
Heterogeneous Mixtures
• Suspensions – particles in solvent so
large that they settle out unless
constantly stirred/agitated
• Colloids – particles of intermediate
size that stay dispersed throughout
a mixture.
• Often appears cloudy
• Use Tyndall Effect to identify
(shine light source through
mixture and particles become
visible in beam of light)
Pure Substances
Fixed composition
• Every sample of pure substance has exactly the
same properties and composition
• Ex: Water is always 11.2% hydrogen and 88.8%
oxygen by mass (determined from periodic table)
Column A
Pure substance or mixture
1. Chlorine
2. Water
3. Soil
4. Sugar water
5. Oxygen
6. Carbon dioxide
7. Rocky road ice cream
8. Alcohol
9. Pure air
10. Iron
Column B
Element or
Compound/Heterogeneo
us or Homogeneous
Introduction
to the Periodic Table
S E C TI ON 1 .3
What is the periodic table?
• Why don’t elements and their symbols always look like
they correspond to each other?
Groups
Periods
Groups & Families
•The vertical columns of the periodic table are called
groups, or families.
•Each group contains elements with similar
chemical properties.
•The horizontal rows of elements in the periodic table
are called periods.
•Physical and chemical properties change
somewhat regularly across a period.
4 Basic
Categories of Elements
Metals
elements to the left of the zigzag line
Properties of metals
•Most solids at room temperature
•Malleable (hammered or rolled into thin sheets)
•Ductile (drawn into a thin wire)
•conduct electricity and heat well
Metals
Gold, copper, aluminum
Nonmetals
right of the zigzag line
an element that is a poor conductor of heat and
electricity
Properties of nonmetals
• many are gases
• solids are brittle
• poor conductors of heat and electricity
Nonmetals
(a) carbon, (b) sulfur, (c) phosphorus (d) iodine
Metalloids
surrounds zigzag line
an element that has some characteristics of metals and
some characteristics of nonmetals
Properties of metalloids
• all metalloids are solids at room temperature
• semiconductors of electricity
•**Aluminum is not a metalloid – it’s a metal!
Noble Gases
Elements in Group 18
Properties of Noble Gases
• Generally unreactive (i.e. “inert”)
• Gases at room temperature
• Glow if electricity is passed through them