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Integrated
Coordinated
Science
End of Year Review
Part 3:
Chemistry
Atomic and Molecular Structure
Standard 1a: Students know how to relate the position of an
element in the periodic table to its atomic number and
atomic mass.
An atom consists of a nucleus
made of protons and neutrons
that is orbited by electrons.
Number of protons, not electrons
or neutrons, determines the
unique properties of an
element.
e
n
-
p
+
p
+
e
-
Atomic and Molecular Structure
Standard 1a: Students know how to relate the position of an
element in the periodic table to its atomic number and
atomic mass.
This number of protons is called the
Atomic number
atomic number.
Elements are
arranged on the
periodic table in
order of increasing
atomic number
from left to right.
6
C
12.01
Atomic and Molecular Structure
Standard 1a: Students know how to relate the position of an
element in the periodic table to its atomic number and
atomic mass.
If elements were
ordered by atomic
mass, this would lead
to misplaced elements
due to differences in
number of neutrons
for isotopes of the
same element affect
the atomic mass but
do not change the
identity of the
element.
Atomic and Molecular Structure
Standard 1b: Students know how to use the periodic
table to identify metals, semimetals, non-metals, and
Halogens
halogens.
Atomic and Molecular Structure
Standard 1c: Students know how to use the periodic table
to identify alkali metals, alkaline earth metals and transition
metals, trends in ionization energy, electronegativity, and
the relative sizes of ions and atoms.
Electronegativity is a
measure of the ability of
an atom of an element to
attract electrons toward
itself in a chemical bond
using range from 0 (no
attractiveness) to 4.0
(highest attractiveness).
Atomic and Molecular Structure
Standard 1c: Students know how to use the periodic table
to identify alkali metals, alkaline earth metals and transition
metals, trends in ionization energy, electronegativity, and
the relative sizes of ions and atoms.
Ionization energy is
the energy it takes to
remove an electron
from an atom.
Atomic and Molecular Structure
Standard 1c: Students know how to use the periodic table
to identify alkali metals, alkaline earth metals and transition
metals, trends in ionization energy, electronegativity, and
the relative sizes of ions and atoms.
Generally in the periodic
table, ionization energy
and electronegativity
increase from left to
right because of
increasing numbers of
protons and decrease
from top to bottom
owing to an increasing
distance between
electrons and the
nucleus.
Atomic and Molecular Structure
Standard 1c: Students know how to use the periodic table
to identify alkali metals, alkaline earth metals and transition
metals, trends in ionization energy, electronegativity, and
the relative sizes of ions and atoms.
Atomic and ionic
sizes generally
decrease from left to
right and increase
from top to bottom for
the same reasons.
Atomic and Molecular Structure
Standard 1d: Students know how to use the periodic
table to determine the number of electrons available for
bonding.
1
Only electrons in
the outermost
energy levels of
the atom are
available for
bonding; this
outermost bundle
of energy levels is
often referred to as
the valence shell
or valence shell of
orbitals.
2
8
3 4 5 6 7
1 or 2
All the elements in a group have the
same number of valence electrons
in their outermost energy level.
Atomic and Molecular Structure
Standard 1e: Students know the nucleus of the atom is
much smaller than the atom yet contains most of its mass.
An atom is made up of the
nucleus (protons and
neutrons) and electron
cloud combined.
The mass of the atom is
densely packed in the
nucleus in the form of
protons and neutrons.
Atomic and Molecular Structure
Standard 1e: Students know the nucleus of the atom is
much smaller than the atom yet contains most of its mass.
The electrons occupy a
large region of space
centered around a tiny
nucleus, and so it is this
region that defines the
volume of the atom.
The electron is almost 2,000
times lighter than the proton;
therefore, the large region of
space occupied by the
electron contains less than
0.1% of the mass of the atom.
Chemical Bonds
Standard 2a: Students know atoms combine to form
molecules by sharing electrons to form covalent or metallic
bonds or by exchanging electrons to form ionic bonds.
If atoms want to keep
their valence electrons,
they will share them in
one of two types of
bonds:
1. Covalent bond: bond
in which non-metals
share electrons between
them
O
C
O
Chemical Bonds
Standard 2a: Students know atoms combine to form
molecules by sharing electrons to form covalent or metallic
bonds or by exchanging electrons to form ionic bonds.
2. Metallic bond: bond
in which metals share
electrons between them
in a loose lattice
If one atom wants to lose
its valence electrons
while the other atom
wants to keep its valence
electrons, they will
exchange or transfer
them in an ionic bond.
Al Al Al
Al Al Al
Na
Cl
Chemical Bonds
Standard 2b: Students know chemical bonds between
atoms in molecules such as H2, CH4, NH3, H2CCH2, N2, Cl2,
and many large biological molecules are covalent.
If atoms are both non-metals, they will be covalent (share electrons).
Many molecules like hydrogen (H2), methane (CH4), ammonia (NH3),
ethylene gas (C2H4), nitrogen (N2), and chlorine (Cl2) are covalent.
NH3
H2
C 2H 4
CH4
N2
Cl2
Chemical Bonds
Standard 2c: Students know salt crystals, such as NaCl, are
repeating patterns of positive and negative ions held
together by electrostatic attraction.
Salt: A chemical
compound formed when a
cation (positive charge)
bonds with an anion
(negative charge)
Example is when sodium
(Na+1) combines with
chlorine (Cl-1) to form table
salt
Chemical Bonds
Standard 2c: Students know salt crystals, such as NaCl, are
repeating patterns of positive and negative ions held
together by electrostatic attraction.
Repeating patterns of
positive and negative
ions form crystals
Salt crystals are held
together by ionic bonds,
which are formed
because of the attraction
between opposite
charges, or electrostatic
attraction.
Acids
and
Bases
Standard 5a: Students know the observable properties of
acids, bases, and salt solutions.
Acid
Acid: substance that
produces hydrogen ions (H+)
in solution
Tastes sour
Feels watery
Conducts electricity
Corrosive/damaging
turns litmus red
pH < 7.0
React with metals to
produce H2 gas
Neutralizes bases
Acids
and
Bases
Standard 5a: Students know the observable properties of
acids, bases, and salt solutions.
Base
Tastes bitter
Feels slippery
Base: substance that produces
hydroxide ions (OH-) in solution
Conducts electricity
Corrosive/damaging
Turn litmus blue
pH > 7.0
Do NOT react with
metals
Neutralizes acids
Acids
and
Bases
Standard 5a: Students know the observable properties of
acids, bases, and salt solutions.
Salt Solution
Salt solution: a crystalline
compound formed from the
neutralization of an acid by
a base containing a metal
Taste salty
Feel watery
Water and salt
acidic, basic or neutral
May be neutral
Acids and Bases
Standard 5c: Students know strong acids and bases fully
dissociate and weak acids and bases partially dissociate.
An acid fully dissociates when all of the H+ ions
separate from the compound.
A base fully dissociates when all of the OH- ions
separate from the compound.
Acids and Bases
Standard 5c: Students know strong acids and bases fully
dissociate and weak acids and bases partially dissociate.
Strong acids or
bases will fully
dissociate.
Weak acids or bases
will partially
dissociate.
Chemical Thermodynamics
Standard 7b: Students know chemical processes can either
release (exothermic) or absorb (endothermic) thermal
energy.
Chemical reactions involve
transfer of energy as heat. This
is called chemical
thermodynamics.
Thermodynamic reactions in
which energy is lost or
released are called
exothermic reactions.
Energy Exits = Exothermic
Chemical Thermodynamics
Standard 7b: Students know chemical processes can either
release (exothermic) or absorb (endothermic) thermal
energy.
Thermodynamic reactions in
which energy is gained or
absorbed are called
endothermic reactions.
Energy Enters = Endothermic
Chemical Thermodynamics
Standard 7c: Students know energy is released when a
material condenses or freezes and is absorbed when a
material evaporates or melts.
When chemicals condense or freeze, energy is
released (to make it colder).Energy released/exits = exothermic
gas
CONDENSATION
FREEZING
EVAPORATION
MELTING
liquid
Energy absorbed/enters = endothermic
When chemicals melt or evaporate, energy is
absorbed (to heat it up).
solid
End of Part 3:
Chemistry