Matter

1
Chapter 2
2
Matter
Matter anything that has mass and takes up space
Mass measure of the amount of matter that an
object contains
Volume measure of the space occupied by the
object
3
Extensive Intensive Properties
What you observe when you examine a sample of
matter is its properties.

• Extensive Property a property that depends on
  the amount of matter in a sample
• Ex. Mass, volume, weight, length

• Intensive Property a property that depends on
  the type of matter in a sample (prefixin means
  within)
• Ex. Hardness, color, odor, luster,
  conductivity, malleability, ductility, freezing
  point, boiling point, melting point, density

4
Substances

• Substance Matter that has a uniform and
  definite composition
• Either an element or a compound
• Also called pure substance
• Rarely found in nature
• Fixed proportions to each other

Examples ?
Diamond ? Water ? Gold ? Copper ?
Sugar ? Nitrogen
5
Mixtures

• Mixture a physical blend of two or more
  substances that are not chemically combined
• Do not exist in fixed proportions to each other
• Most natural substances are mixtures
• Can usually be separated back into its original
  components

Examples ?
Concrete ? Soil ? Salt water ? Milk ?
Coke ? Gasoline ? Fruit salad ?
Atmosphere
Examples ?
Concrete ? Soil ? Salt water ? Milk ?
Coke ? Gasoline ? Fruit salad ?
Atmosphere
6
Two Types of Mixtures

• Homogeneous Mixture (solution) a mixture in
  which the composition is uniform throughout.
• Consists of a single phase
• Cant see them separately or separate them
  physically

Examples ? stainless steel ? air ?
olive oil ? vinegar
7
Two Types of Mixtures

• Heterogeneous Mixture a mixture in which the
  composition is not uniform throughout.
• Consists of a two or more phases

Examples ? chicken soup ? oil vinegar
mixed ? milk ? rice crispy treats
8
Separating Mixtures
Differences in physical properties can be used to
separate mixtures
Filtration process that separates a solid from
a liquid
Examples ? coffee filters ? draining
pasta
9
Separating Mixtures
Distillation process of boiling a liquid to
produce a vapor and then condensing the vapor
into a liquid
Example ? separating water from other substances
in the water
10
States of Matter
1. Solid
3. Gas
2. Liquid
11
States of Matter
Solid Definite shape Definite volume Not easily
compressed

• Characteristics
• Does not take the shape of the container
• Particles packed tightly together, and often in
  orderly arrangement
• Almost incompressible
• Expands only slightly when heated

12
States of Matter
Liquid Indefinite shape Definite volume Not
easily compressed

• Characteristics
• Take the shape of the container in which it is
  placed
• Particles in close contact, but arrangement of
  particles is not orderly (can flow past each
  other)
• Almost incompressible
• Expands slightly when heated

13
States of Matter
Gas Indefinite shape indefinite volume Easily
compressed

• Characteristics
• Take the shape of the container in which it is
  placed
• Can expand to fill any volume
• Particles are much farther apart
• Easily compressed into a smaller volume

14
Physical Change
Physical Change Some properties of a material
change, but the composition of the material does
not change

• Examples
• Changes of state such as boiling water,
  condensation (boil, freeze, melt, condense)
• Physical deformation such as cutting, denting,
  stretching, breaking, crushing

15
Chemical Change
Chemical Change A change that produces matter
with a different composition than the original
matter

• Examples
• Silver spoon tarnishes
• Metal rusts ? Methane burns
• Methane burns ? Sugar ferments
• Burn, rot, rust, decompose, ferment, explode,
  corrode usually mean a chemical change

16
Elements

• Element simplest form of matter that has a
  unique set of properties.
• cannot be broken down into simpler substances

• Examples
• Hydrogen
• Nitrogen
• Oxygen

17
Compounds

• Compound substance that contains two or more
  elements chemically combined in a fixed
  proportion.
• Compounds can be broken down into simpler
  substances by chemical means

• Examples
• Sugar (C12H22O11)
• Salt (NaCl)
• Water (H2O)

18
Breaking Down Compounds
A chemical change is required to breakdown
compounds into simpler substances

• Some methods
• Heating
• Sugar heat Carbon Water
  compound element
  element

Electric current Water electricity
Hydrogen Oxygen compound
element element

19
Properties of Compounds
In general, properties of compounds are quite
different from those of their component elements.

• Example
• Compound ---- Table Salt (NaCl)
• Element ---- Sodium (Na) soft, gray metal
• Element ---- Chlorine (Cl) pale yellow-green
  poisonous gas.

20
Classifying Matter
Any sample of matter is either an element, a
compound, or a mixture
Matter
Substance Definite composition
Mixture Variable composition
Can be separated physically
Can be separated chemically
Element Simplest form
Compound
Homogeneous Mixture Uniform also called a
solution
Heterogeneous Mixture Nonuniform Distinct phases
Silver
Salt
Stainless Steel
Cement
21
Chemical Symbols
Each element on the periodic table is represented
by a one or two letter chemical symbol.

• The first letter of a chemical symbol is always
  capitalized.

• When a second letter is used, it is lowercase

• Examples
• Na Sodium Au - Gold
• C - Carbon K - Potassium

22
Symbols Derived From Latin
Sodium Na
Potassium K
Antimony Sb
Copper Cu
Gold Au
Silver Ag
Iron Fe
Lead Pb
Tin Sn
23
Physical Properties
Physical Property a quality or condition of a
substance that can be observed or measured
without changing the substances composition

• Examples
• ? Appearance ? Density
• ? Texture ? Malleability
• ? Color ? Boiling Point
• ? Odor ? Melting Point
• ? Conductivity ? Hardness

24
Chemical Property

• Chemical Property
• Ability of a substance to undergo a specific
  chemical change
• Chemical properties can be observed only when a
  substance undergoes a chemical change.

Examples Gasoline -- burns in air Iron -- rusts
Baking Soda -- reacts with vinegar Copper --
rusts in water Table salt -- does not react with
vinegar
25
Recognizing Chemical Changes
Words such as burn, rot, rust, decompose,
ferment, explode, and corrode usually signify a
chemical change.
During a chemical change, the composition of
matter always changes.
Examples Gasoline -- burns in air Iron -- rusts
Baking Soda -- reacts with vinegar Copper --
rusts in water Table salt -- does not react with
vinegar
26
Recognizing Chemical Changes

• Possible Clues
• Transfer of energy
• A change in color
• The production of gas
• The formation of a precipitate

Precipitate solid that forms and settles out of
a liquid mixture Ex. ring of soap scum in your
bathtub
The only way to be sure a chemical change has
occurred is to test the composition of a sample
before and after the change
27
Law of Conservation of Mass
During any chemical reaction, the mass of the
products is always equal to the mass of the
reactants.

• Example
• 2H2 O2 2H20
• 2g 2g 4g
• reactants product