GOLD ATOMS
WATER ATOMS
What is the diagram
hanging in the front
of the room? What
does it show?
Let’s watch…..
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A pure substance made of only one kind of atom.
Represented by symbols and organized on a
Periodic Table of Elements.
Let’s predict
the elements
shown.
• CALLED PERIODS
• We read the periodic table from
left to right.
• Increasing atomic mass from left to right.
(the atoms get bigger)
• CALLED GROUPS OR FAMILIES
•They share the same reactivity
and properties.
(like brothers and sisters)
Let’s check out how families are similar!
Nobel Gases
Alkali Metals
METALS
NONMETALS
Let’s predict! What elements are found in all living things (Including us)?
MATTER
ATOMS
PROTONS
NEUTRONS
ELECTRONS
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What are the three subatomic particles that
atoms are made of?
(Hint: Look at your notes if you need to)
Protons
Neutrons
Electrons
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We will be investigating the first 18 elements
since they are the most common to biology.
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Let’s see what your previous knowledge is!
Working with a partner make a model of an
atom using the clay at your desk.
Use the plate as the “nucleus”.
Protons = red (2)
Neutrons = purple (2)
Electrons = orange (2)
Electron (-) negative
Orbital / Energy Level
Nucleus:
Protons (+) positive
Neutrons (o) Neutral
The atomic number gives you the number of
protons
_____________of
the element.
electrons
This number equals the number of ____________.
Let’s practice!
Gold has an atomic number of 79 –
How many Protons and Electrons does it have?
79 protons
79 electrons
Oxygen has an atomic number of 8 –
How many Protons and Electrons does it have?
8 protons
8 electrons
To calculate the neutrons of an element
Step 1: Round the mass number to the whole number
Step 2: Subtract the atomic number from the mass number
Let’s practice!
Helium: Mass Number is:
Atomic Number is:
Chlorine: Mass Number is:
Atomic Number is:
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Also called “orbitals” or “shells”.
Electrons are found in the orbitals.
Electrons go around the nucleus of the atom.
N
u
c
l
e
u
s
P+
n0
2
e-
8
e-
18
8
ee-1
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The electrons in the last shell or energy level
of an atom.
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Determine the properties and chemical
reactivity of the element and participate in
chemical bonding.
 Let’s look at the first 18 elements on
the periodic table. These are the
elements most common to biology.
 We will color code the subatomic
particles and include the orbitals or
energy level for each element.
 Let’s do one together!
1.
Draw nucleus, shade in &
include # of p+ c
2.
Draw in the energy levels
& electrons (e-)
a. 1st Energy Level = Blue
b. 2nd Energy Level = Red
c. 3rd Energy Level = Green
#p+
#p+
#n0
Name
Atomic #
Symbol
Nucleus
Orbital
2
8
18
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Build an accurate model of any element you
choose, from 2-18.
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Use a plate as the nucleus
Use red pom poms as protons
Use black pom poms as electrons
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Be prepared to explain your model
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