Chemistry I
Mr. Patel
SWHS
 Continue
to Learn Major Elements and
Symbols
 Properties of Matter (2,1, 2,2, 2,3)
 Physical and Chemical Changes (2.1, 2.4)
 Inter-/Intra-molecular Forces
 States of Matter (13.2, 13.2, 13.3)
 Kinetics/KMT, Phase Change (13.1, 13.4)
 Remember
matter is anything that has
mass and occupies volume.
 Matter
is described using properties that
are extensive or intensive properties.
 Extensive
Property – a property that
depends on the amount of matter in a
sample. (Changes with amount)
• Mass – measure of the amount of matter an
object contains
• Volume – measure of the space taken up
• Other examples: energy, weight, length, area
 Intensive
Property – a property that does
NOT depend on the amount of matter
• Density –
D = mass/volume
matter per unit volume
• Other examples: hardness, melting/freezing
point, concentration, viscosity
1.
The Boiling point of
water is 100OC.
1.
Intensive
2.
The mass if 300 kg.
2.
Extensive
3.
The length is 30 m.
3.
Extensive
4.
The density of water
is 1.0 g/mL.
4.
Intensive
 All
matter can be divided into substances
and mixtures
 Substance
– uniform and definite
composition
 Every
sample of a substance has
identical intensive properties. Why?
Matter
Anything that has
mass and volume
Substance
Constant
Composition;
All particles identical
Ex: Water, Helium
Mixture
Physically
Separate
Variable
Composition;
2 or more substances
Ex: Sand, Soil

Substances can be classified as elements or
compounds

Element – simplest form of matter with unique
set of properties (all atoms same)
• Ex: Gold, Hydrogen, Oxygen (on periodic table)

Compound – two or more elements chemically
combined in fixed ratios
• Ex: Water, salt, baking soda

Compounds can be chemically separated to
elements
Matter
Anything that has
mass and volume
Substance
Mixture
Constant
Composition;
All particles identical
Ex: Water, Helium
Element
Made up of
identical atoms;
on Periodic
Table
Ex: Zinc, Uranium
Physically
Separate
Compound
Chemically
Separate
Made up of 2 or
more elements;
combined
chemically
Ex: Carbon dioxide
Variable
Composition;
2 or more substances
Ex: Sand, Soil
 Mixture
– a physical blend of two or more
components (substances)
 Heterogeneous
Mixture – the
composition is not uniform throughout
• Ex: soil, chicken noodle soup
 Homogeneous
Mixture – (solution)
composition is uniform throughout
• Ex: salt water, alloys (solid in solid)
 Mixtures
can be separated physically
 Filtration
– solid from liquid
 Distillation
–
liquid from
liquid or solid
Steel = Iron + Carbon
Matter
Anything that has
mass and volume
Substance
Mixture
Constant
Composition;
All particles identical
Ex: Water, Helium
Element
Made up of
identical atoms;
on Periodic
Table
Ex: Zinc, Uranium
Physically
Separate
Compound
Chemically
Separate
Made up of 2 or
more elements;
combined
chemically
Ex: Carbon dioxide
Variable
Composition;
2 or more substances
Ex: Sand, Soil
Heterogeneous
Homogenous
Uneven Distribution;
easy to separate
Ex: Vegetable Soup
Uniform Distribution;
called solution
Ex: Tap water, Steel
 Physical
Property – measured properties
that do not change the nature of the
sample
• Ex: Boiling Point, Density, Mass
 Physical
Change – some properties may
change but the composition of the
material does not change
• Ex: Boiling, Freezing, Cutting, Splitting
• Can be Reversible or Irreversible
 Physical
Changes do not involve
chemical reactions
• No Breaking or Forming Chemical Bonds
• Substance is the same before and after the
change
 Chemical
Property – the ability of a
substance to undergo a chemical
reaction
• Ex: Flammability, Combustibility, decomposition
 Chemical
Change – the composition of
matter will always change
• Ex: Burning, exploding, reacting, rusting, rotting
• Also called a chemical reaction
 Clues
for a chemical reaction:
1.
2.
3.
4.
Transfer of Energy – heat, sound, light
Color Change
Gas Production
Formation of Precipitate – solid that settles
out of a liquid mixture
•
Don’t confuse for a physical change
 Law
of Conservation of Mass – mass is
neither created nor destroyed; it is only
transformed.
 The
mass before a reaction must always
equal the mass after a reaction
1.
2.
3.
4.
5.
Burning Gasoline
Evaporation of
Water
Stripping a Copper
Wire
Mold Growing on
Yogurt
Alka-Setlzer tablets
2.
Chemical
Physical
3.
Physical
4.
Chemical
5.
Chemical
1.
INTERMOLECULAR FORCES




Forces between individual
molecules
Strong by Numbers
Ex: Hydrogen Bonding,
Dipole forces, Dispersion
Forces
Contribute to Physical
Changes
INTRAMOLECULAR FORCES




Forces within a specific,
individual molecule
Very Strong
Ex: Ionic Bond, Covalent
Bond, Metallic Bond
Contribute to Chemical
Changes
 There
are four states of matter
1. Solid
2. Liquid
3. Gas
4. Plasma
 We
focus mostly on the first three
 Definite
Shape
 Definite Volume
 Incompressible
 Particles
tightly
packed - ordered
 Vibrations
(Not Fluid)
 Indefinite
Shape
 Definite Volume
 Incompressible
 Particles
in contact but
disorderly packed
 Particles
flow (Fluid)
 Indefinite
Shape
 Indefinite Volume
 Highly
Compressible
 Particles
far apart;
little contact; collisions
 Particles
flow (Fluid)
 Particles:
• Have a lot of space between them
• Are in rapid motion
• Exert Pressure = Billions of collisions
• Spontaneously expands
 There
are 6 state/phase changes
 Some
change require heat (energy)
 Endothermic
 Exothermic
– requires heat
– releases heat
 Solid
to Liquid
 Endothermic
 Particles
have
enough energy to
begin to flow
 Melting
Point – temp
when liquid forms
 Liquid
to Solid
 Exothermic
 Particles
have lose
energy and slow
down
 Freezing
Point – temp
when Solid forms
 Mpt
= Fpt
 Liquid
to Gas
 Endothermic
 Particles
have
enough energy to
break away
 Boiling
Point – temp
when gas forms
 Gas
to Liquid
 Exothermic
 Particles
begin to
stick
 Same
as Bpt
 Solid
to Gas
 Endothermic
 NO
liquid stage
 Ex: Dry
Ice
 Gas
to Solid
 Exothermic
 No
Liquid Stage
 Ex: Snowing
 The
temperature at which a substance
undergoes a phase change depends on
the pressure.
 Think
about boiling an egg on top of Mt.
Everest. Pressure is lower so water boils
at a lower temperature meaning it will
take longer to cook the egg (enough
heat)
A
Phase Diagram outlines the
relationship between temp and pressure.
 At
a specified temp and pressure, we can
determine what state of matter the
substance is in.
 There
are two important points
 Triple
Point – where solid, liquid, gas
coexist
 Critical
 Each
Point – no phase boundary exist
line represents two states
coexisting