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STAAR Reporting Category 1
Matter & Energy
Atoms and Elements
The Structure of an Atom
electron (-)
neutron (o)
electron
cloud
++
+ + nucleus
++
Proton (+)
Location and Mass of
Atomic Particles
Inside the Nucleus
Protons with a POSITIVE
charge
AND
Outside the Nucleus
Electrons with a NEGATIVE
charge
VERY, VERY tiny and do not
contribute to the mass of the
Neutrons with a NEUTRAL atom
charge (no charge)
Both have about the same
mass
It takes 2000 electrons to equal
the mass of one proton or
neutron
Elements are listed on the
Periodic Table
Atomic Number
Number of PROTONS and
determine which element the
atom is
Atomic Mass
the number of PROTONS + NEUTRONS
How do I calculate # of NEUTRONS???
First, round the atomic mass to the
nearest whole number
Round to 28
Then, subtract the Atomic
number (# protons) from the
Atomic mass (total # protons
and neutrons
28 (Atomic mass)
-14 (Atomic number)
14 NEUTRONS
Is there an EASIER way to
remember all of this?
All you have to do is remember:
A=P=E
M-A=N
A=P=E
Atomic Number
=
If I know ONE,
I know them
Protons
ALL!!
=
Electrons
M-A=N
Mass
Atomic Number
=
Neutrons
PRACTICE TIME
Use your Periodic Table!!
Symbol
Atomic
#
Mass
#
#
Protons
#
Neutrons
#
Electrons
He
2
4
2
2
2
Li
3
7
3
4
3
N
7
14
7
7
7
Electrons and Bohr Diagrams
1) Find your element on the periodic table.
2) Determine the number of electrons –
remember, it is the same as the atomic
number.
3) This is how many electrons you will draw.
Bohr Diagrams
6P
6N
Draw a nucleus with the
number of protons and
neutrons inside.
Bohr Diagrams
6P
6N
1) Add the electrons.
2) Carbon has 6
electrons.
3) The first shell can
only hold 2
electrons. Always
start in the first shell
Bohr Diagrams
6P
6N
1) Since you have 2
electrons already
drawn, you need to
add 4 more.
2) These go in the 2nd
shell.
Bohr Diagrams
6P
6N
1) Check your work.
2) You should have 6
total electrons for
Carbon.
3) Only two electrons
can fit in the 1st shell.
4) The 2nd and 3rd shells
can hold up to 8
electrons.
Bohr Diagrams
Try the following
elements on your own:
a)
b)
c)
d)
e)
f)
H
He
O
Al
Ne
K
Bohr Diagrams
Try the following
elements on your own:
1P
a)
b)
c)
d)
e)
f)
H – 1 electron
He
O
Al
Ne
Na
Bohr Diagrams
Try the following
elements on your own:
2P
2N
a)
b)
c)
d)
e)
f)
H
He - 2 electrons
O
Al
Ne
Na
Bohr Diagrams
Try the following
elements on your own:
8P
8N
a)
b)
c)
d)
e)
f)
H
He
O - 8 electrons
Al
Ne
Na
Bohr Diagrams
Try the following
elements on your own:
13 P
14 N
a)
b)
c)
d)
e)
f)
H
He
O
Al - 13 electrons
Ne
Na
Bohr Diagrams
Try the following
elements on your own:
10 P
10 N
a)
b)
c)
d)
e)
f)
H
He
O
Al
Ne - 10 electrons
Na
Bohr Diagrams
Try the following
elements on your
own:
11 P
12 N
a)
b)
c)
d)
e)
f)
H
He
O
Al
Ne
Na - 11 electrons
Valence Electrons
• Found on the outermost energy
level
–Determine how an element will
react chemically
Lewis Structures
How many valence electrons does nitrogen
have?
5
Learning Check
How many valence electrons in each atom?
Heliu
m
Oxygen
Sodium
2
6
1
Charges of Atoms
Most atoms have a NEUTRAL CHARGE since
they have equal numbers of protons (+) and
electrons (-).
Some atoms gain or lose electrons to become
IONS.
IONS are not neutral and the atom becomes
positively or negatively charged. Let’s see how
this works...
in an atom,
protons ( + ) are in
the center
and electrons ( )
are on the outside
+ ++
+ +
only electrons ( )
can be added
or taken away
+ ++
+ +
this is an atom with
5 electrons and
5 protons
+ ++
+ +
the atom is neutral
net charge = zero
+ ++
+ +
5 (-) and 5 (+) = zero charge (neutral)
charge = ?
6 (-) and 5 (+) = -1
+ ++
+ +
charge = ?
3 (-) and 5 (+) = +2
+ ++
+ +
WHEN REMOVING ELECTRONS
THE RESULTING CHARGE IS POSITIVE
neutral
+1
WHEN ADDING ELECTRONS
THE RESULTING CHARGE IS NEGATIVE
neutral
-2
Elements are substances:
• that cannot be broken down into
other substances
• that are made of atoms with the
same number of protons in the
nucleus
Elements are ORGANIZED
on the Periodic Table
Elements with similar properties are placed in the
same group in the periodic table.
The stair-step line separates the elements into
metals and nonmetals.
Groups of Elements
Alkali Metals
• Group 1, highly reactive, 1 valence electron
• Soft metals with low melting points
The Periodic Table of Elements
1
1
2
3
4
5
6
7
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
18
13
3
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
Alkaline Earth Metals
• Group 2, reactive, 2 valence electrons
• Hard metals with high melting points
The Periodic Table of Elements
1
1
2
3
4
5
6
7
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
18
13
3
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
Transition Metals
• Group 3-12, variable # of valence electrons
• Unpredictable, don’t follow “reactivity” rules
The Periodic Table of Elements
1
1
2
3
4
5
6
7
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
18
13
3
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
Halogens
• Group 17, highly reactive, 7 valence electrons
• Form “salts”
The Periodic Table of Elements
1
1
2
3
4
5
6
7
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
18
13
3
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
Noble Gases
• Group 18, full outer shells (2 in He and 8
in others)
• NON-REACTIVE
The Periodic Table of Elements
1
1
2
3
4
5
6
7
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
18
13
3
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
Rare Earth Elements
• Group 3, Period 6 and 7
• Special group of transition metals
• Many are synthetic and/or radioactive
The Periodic Table of Elements
1
1
2
3
4
5
6
7
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
18
13
3
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
Metalloids
• Non-metal elements that are conductors of
heat and electricity
The Periodic Table of Elements
1
1
2
3
4
5
6
7
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
18
13
3
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
Periodic Trends
• Elements are arranged into horizontal rows called
PERIODS
• Elements within a period have the same number of
ENERGY LEVELS
The Periodic Table of Elements
1
1 energy level
1
2 energy levels
2
3 energy levels
3
4 energy levels
5 energy levels
4
6 energy levels
6
7 energy levels
7
5
18
H 2
Li Be
Na Mg 3
K Ca Sc
Rb Sr Y
Cs Ba Lu
Fr Ra Lr
13
4
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu AmCm Bk Cf Es Fm Md No
He
Ne
Ar
Kr
Xe
Rn
• Elements are arranged in vertical columns called
GROUPS
5
6
7
4
Sc
Y
Lu
Lr
Ti
Zr
Hf
Rf
5
6
7
8
V Cr Mn Fe
Nb Mo Tc Ru
Ta W Re Os
Db Sg Bh Hs
9
Co
Rh
Ir
Mt
13
14
15
16
17
C
Si
Ge
Sn
Pb
N
P
As
Sb
Bi
O
S
Se
Te
Po
F
Cl
Br
I
At
B
10 11 12 Al
Ni Cu Zn Ga
Pd Ag Cd In
Pt Au Hg Tl
Ds Rg
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
8 valence electrons
7 valence electrons
4
3
6 valence electrons
3
5 valence electrons
2
H 2
Li Be
Na Mg
K Ca
Rb Sr
Cs Ba
Fr Ra
4 valence electrons
1
The Periodic Table of Elements
3 valence electrons
1
2 valence electrons
1 valence electron
– have same number of VALENCE ELECTRONS
– share similar CHEMICAL properties
18
He
Ne
Ar
Kr
Xe
Rn
Metal Properties
•
•
•
•
•
Shiny solids
Ductile (able to be stretched)
Malleable (able to be shaped)
Good conductors of heat and electricity
Magnetic
Nonmetal Properties
•
•
•
•
May be solids, liquids or gases
Dull, brittle solids
Poor conductors of heat and electricity
Non-magnetic
Metalloid Properties
• Nonmetals with properties of both metals and non-metals
• Weak conductors of heat and electricity
Atomic Theory
 Atoms are building blocks of elements
 Atoms in each unique element are the same.
(Ex: Every oxygen element has the same # of protons)
 Atoms are different from atoms of other elements
(Ex: Hydrogen has a different # of protons than oxygen)
 Two or more different atoms bond in simple ratios to
form compounds
(Ex: Hydrogen & oxygen can
chemically combine to form water- H2O )
Writing Chemical Symbols
1. First letter is capitalized
2. Second letter is lower case
3. NO period at the end
H Cl O Hg Fe Sn C He
Does it really matter?
Co or CO
Co = cobalt
Alloys for metals used
in jet turbines
CO
carbon
oxygen
carbon monoxide
Colorless
Odorless
Poisonous gas
Compounds
2 or More Elements
Chemically Combined
Hydrogen
2-H: 1-O
Hydrogen
Oxygen
Ratio
2:1
H
H
O
H2O
1 is not
shown
Formulas use element symbols
with subscript numbers
Water
Change the ratio
Change the substance
Hydrogen 2:2
Peroxide H2O2
Subscript numbers
http://www.wonderquest.com/images/2003-08-08-peroxide.jpg
No subscripts??
1Na
NaCl
Salt
1Cl
How many elements? 2
Chemical Changes
A chemical change is a change in which both the
physical and chemical properties of the
original substance are changed. The new
substance has new physical and chemical
properties.
Burning is a
chemical
change.
A chemical change is the result of a
Chemical Reaction.
A chemical reaction occurs when
atoms separate, come together, or
rearrange to form new substances
with new properties.
Example of a Chemical Reaction
Reactant + Reactant
 Product
(goes to)
carbon + oxygen 
carbon dioxide
(has different properties)
C + O2  CO2
Is the product the same as the reactants?
No, the atoms have been rearranged.
For Example…
A chemical reaction takes place during
photosynthesis.
6CO2 + 6H2O  C6H12O6 + 6O2
Carbon dioxide reacts with water to form
glucose (a sugar) and oxygen.
copper + oxygen  copper oxide
2 Cu
O2
Cu O
Cu O
2 CuO
CuO
CuO
balanced
2 copper atoms
2 oxygen atoms
in a molecule (O2)
2 copper atoms
2 oxygen atoms
2 copper atoms
2 copper atoms
=balanced=
2 oxygen atoms
2 oxygen
atoms
Since nothing is lost or gained, there is
no loss or gain in mass (atoms).
You can say the equation is balanced.
The Law of conservation of mass states that
matter cannot be created or destroyed in
any chemical reaction
The atoms in the reactants are rearranged
to form new compounds, but none of the
atoms disappear, and no new atoms are
formed.
H
H
H
H
Reactants
O
O
Products
Remember that atoms don’t
change in a chemical reaction.
• The number and kinds of atoms
present in the reactants of a
chemical reaction are the same as
those present in the products. When
stated this way, it becomes the law
of conservation of atoms.
So: Chemical equations are balanced, when the
numbers and kinds of atoms on each side of
the reaction arrow are equal.
H
H
H
H
O
H
O
O
H
H
Reactants
Products
4 Hydrogen
4 Hydrogen
2 Oxygen
2 Oxygen
H
O
Coefficients, the numbers placed in
front of formulas to balance
equations, indicate the number of
particles present in the reaction. If a
number is not present it is
understand that 1 is the coefficient.
2 H2 + O2  2 H2O
2
2
The number of oxygen atoms are not the
same so the equation is balanced with
coefficients.
Notice that the number of
hydrogen and oxygen atoms
are equal
The same number of each kind of atom must
be on the left side of the arrow as are on the
right side when an equation is balanced.
Al
Al
Al
Al
O O
O O
O O
When an equation is balanced the number of
reactant atoms will always equal the number of
product atoms and atoms are conserved
O Al O Al O
O Al O Al O
O O
Al Al O O
AlAl O O
Chemical Equations
• Many times it may seem that things we use disappear
over time. For example, gasoline in the car.
• Elements of gasoline are merely re-arranged through
a chemical reaction. Gasoline  CO2 and H2O
• The number of each type of element and their masses
remain unchanged (balanced) in a chemical reaction.
(Law of Conservation of Mass)
• A chemical equation is a way to describe or
represent what goes on in a chemical reaction and
follows the Law of Conservation of Mass.
• Matter cannot be created or destroyed – ONY
rearranged into different substances.
Chemical and Physical
Change
Organic Compounds
• Compounds that includes CARBON along
with other element(s) hydrogen, nitrogen,
phosphorous, and or sulfur.
• Nucleic Acid (DNA), Carbohydrates,
Proteins, & Starch.
Is it Organic?
C6H12O6
YES
Ca3Si2O7
no
NaCl
no
C3H8
YES
Fe2O3
no
C5H11NO2S
CuSO4
CH3COOH
Ca5(PO4)3OH
C27H46O
YES
no
YES
no
YES
The transfer of energy from the sun
to producer to primary consumer to
secondary consumer to tertiary
consumer can be shown in a FOOD
CHAIN.
The arrow shows the flow of energy,
first from the sun to the producers
and then to each organism in the food
chain.
Food Webs:
• Are interconnected food
chains
• They show the feeding
relationships in an
ecosystem
• Arrows point in
direction of energy flow
Another way of showing the transfer
of energy in an ecosystem is the
ENERGY PYRAMID.
Energy pyramids show
.1%
1%
10%
100%
• That the amount of available
energy decreases down the
food chain
• Only 10 % of the energy is
passed to the next level
• It takes a large number of
producers to support a small
number of primary
consumers
• It takes a large number of
primary consumers to
support a small number of
secondary consumers
What is density?
• Density is a comparison of how much
matter there is in a certain amount of space.
What is density?
• Density = mass OR
volume
• Units for density: g
OR
g
mL
mass ÷ volume.
ALWAYS
REMEMBER
cm3
UNITS!
Density Problems
• Frank has a paper clip. It has a mass of 9 g and a
volume of 3 cm3. What is its density?
D=m
v
D=9g
3 cm3
D = 3 g/cm3
• Frank also has an eraser. It has a mass of 3 g, and a
volume of 1cm3. What is its density?
D=m
v
D=3g
1 cm3
D = 3 g/cm3
• Jack has a rock. The rock has a mass of 6 g and a
volume of 3 cm3. What is the density of the rock?
D=m
v
D=6g
3 cm3
D = 2 g/cm3
• Jill has a gel pen. The gel pen has a mass of 8 g and
a volume of 2 cm3. What is the density of the pen?
D=m
v
D=8g
2 cm3
D = 4 g/cm3
• Al’Licia has a watch. It has a mass of 4 g and a
volume of 2 cm3. What is the density of the watch?
D=m
v
D=4g
2 cm3
D = 2 g/cm3
• Mia has a wallet. It has a mass of 15 g and a
volume of 5 cm3. What is the density of the wallet?
D=m
v
D = 15 g
5 cm3
D = 3 g/cm3
√ Check your
understanding
1. The symbol for carbon is –
A Ca
B
c
C
CA
D C
2. How many protons are in
an atom of sodium?
A 11
B
12
C
23
D 34
3.How many neutrons are there,
if the mass number is 1 and
the atomic number is 1?
A 3
B
2
C
1
D 0
4.How many electrons are in
an atom of Cl?
A 17
B
18
C
35
D 0
5.Which of the following is
a chemical formula?
A H
B
O
C
H2O
D h2o
6.How many different elements
are in baking soda, NaHCO3 ?
A 6
B
5
C
4
D 3
7. Which of the following situations contains an
example of a chemical reaction?
A
B
C
D
Ice forming after water is placed in a freezer
Watercolor paint drying on paper
A sugar cube dissolving in a glass of water
A bicycle rusting after it is left in the rain
C6H12O6 + 6 O2 
6 H2O
+
6 CO2
HCl + NaOH  H2O + NaCl
8.
Based on the data above, which statement is not true
about chemical equations?
A. Products are the rearrangement of atoms from the reactants.
B. There are always more atoms on the reactant side of the equation
than the product side.
C. The types of atoms in the products will be the same as the types
of atoms in the reactants.
D. The mass and number of reactant atoms always equals the mass
and number of product atoms.
9. Which chemical reaction is balanced?
A. C + O2  2 CO2
B. 2 C + O2  2 CO2
C. 2 C + 2 O2  2 CO2
10. Which chemical reaction is balanced?
A. HBr + Mg  H2 + MgBr2
B. 2 HBr + Mg  H2 + MgBr2
C. 2 HBr + 2 Mg  H2 + 2 MgBr2