Download Notes – Chapter One Chemical Foundations

Notes – Chapter Two
Atoms, Molecules, and
Ions
Section 2.2
Fundamental Chemical Laws
 Law of conservation of Mass
 Law of Definite Proportions
 Law of Multiple Proportions
Section 2.3 Dalton’s
Atomic Theory
 Each element is made up of tiny particles called atoms
 The atoms of a given element are identical; the atoms
of different elements are different in some fundamental
way or ways
 Chemical compounds are formed when atoms of
different elements combine with each other. A given
compound always has the same relative numbers and
types of atoms
 Chemical reactions involved reorganization of the
atoms – changes in the way they are bound together.
The atoms themselves are not changed in a chemical
reaction.
Section 2.3
Dalton’s Atomic Theory –
Slide 2
Avogadro’s hypothesis
- At the same temperature and pressure, equal
volumes of different gases contain the same
number of particles.
Under the above conditions, the volume of a
gas is determined by the number of molecules
present, not by the size of the individual
particles.
Section 2.4 Early
Experiments to Characterize
the Atom
 The Electron
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Cathode-ray tubes
J.J. Thomson
Robert Millikan
Radioactivity
 The Nuclear Atom
 Ernest Rutherford
Section 2.5
The Modern View of Atomic
Structure
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Protons
Neutrons
Isotopes
Atomic Number
Mass Number
Writing symbols for atoms
Section 2.6
Molecules and Ions
 Chemical Bonds
 Covalent bonds
 Molecules
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Chemical formula
Structural formula
Space-filling model
Ball-and-stick models
 Ionic bonds
 Ions
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Cation
Anion
Ionic bonding
Ionic solid or salt
Polyatomic ions
Section 2.7
An Introduction to the
Periodic Table
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Periodic table
Metals
Nonmetals
Groups (families)
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Alkali metals
Alkaline earth metals
Halogens
Noble gases
 Periods
Section 2.8
Naming Simple Compounds
 Binary compounds
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Type 1
Type 2
Ionic compounds with Polyatomic ions
Type 3
 Formulas with Names
 Acids
Binary Ionic Compounds
Type 1
1. The cation is always named first and
the anion second.
2. A monatomic cation takes its name
from the name of the element.
3. A monatomic anion is named by taking
the root of the element named and
adding - ide.
Binary Ionic Compounds –
Type 2
 These compounds follow the same rules as
Type 1 with the exception that the cation is a
metal with multiple charges.
 The charges of the cation must be written in
the formula using a Roman numeral. Example,
Fe +2 is represented as Iron (II).
 For cations that come from the transition metal
section with only one charge do not use roman
numerals.
Ionic Compounds with
Polyatomic Ions
 Polyatomic ions may be either cations or
anions depending on their charge.
 Polyatomic ions state their name when in
compounds. For compounds that contain two
polyatomic ions, both names are stated without
an ending added.
 Oxyanions – anions combined with the same
element and different numbers of oxygen
atoms.
Binary Covalent
Compounds – Type 3

Compounds formed from
two nonmetals.

Naming these compounds
1.
2.
3.
4.
The first element in the
formula is named first, using
the full element name.
The second element is named
as if it were an anion.
Prefixes are used to denote
the numbers of atoms
present.
The Prefix mono- is never
used for naming the first
element.
Prefixes Used to Indicate
Number in Chemical Names
Prefix
Mono
Di
Tri
Tetra
Penta
Hexa
Hepta
Octa
Nona
Deca
Number Indicated
1
2
3
4
5
6
7
8
9
10
Formulas From Names

When given the name of a compound
complete the following steps in order to
write the formula correctly.
1. Identify if the compound is covalent or ionic.
2. If ionic, identify the charges for both elements.
Use subscripts to balance the charges of the
cation and anion.
3. If covalent, write the compound using prefixes.
If a prefix is attached, that prefix is the subscript
for that element.
Acids
Does the anion
contain oxygen?
No
Yes
Hydro –
+ anion root
+ - ic
Hydro(anion root)ic acid
Check the ending
of the anion
-ite -ate
Anion or element root
+ -ous
(root)ous acid
Anion or element root
+ - ic
(root)ic acid
Oxyanionic Acids
 The names of oxyanionic acids are based on the
amount of oxygen atoms in each compound. (See
chart on page 72)
 Example of an oxyanioic acid with four different
amounts of oxygen.
Acid
Anion
Name of Acid
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Perchlorate
Chlorate
Chorite
Hypochlorite
Perchloric acid
Chloric acid
Chlorous acid
Hypochlorous acid
HClO4
HClO3
HClO2
HClO