Science 8
Laboratory Activity
Enduring Understandings
Resource use is determined by physical and chemical properties.
What is a Metal?
Concepts Important to Know and Understand
physical and chemical actions, properties of matter
EQ: What stories do rocks tell?
Broad Brush Knowledge
periodic table, chemical formulas
Targeted Skills
Thinking and Reasoning
 Critical Thinking
 compare/contrast
 Creative Thinking
 classify
Core Objectives
15. Identify physical and chemical properties used to classify
matter and to determine everyday applications.
16. Demonstrate that substances may react chemically to form
new substances which can be represented in chemical
equations.
Expert Information: The periodic table is organized according to energy levels and valence
electrons. Examine
An energy
level isand
thechemical
number properties
of rings ofof
electrons
around
the nucleus
of an atom.
Purpose
physical
elements.
To determine
properties
usedRows
to
or periodsclassify
on theelements
periodic on
table
are arranged
the periodic
table. based on energy levels. Groups or columns are
arranged based on the number of valence, or outermost, electrons. Look at group 13. It includes
carbon, silicon, and germanium. Notice that it is also called group 4A because these elements have
4 valance electrons. The number of valence electrons an atom has determines its physical and
chemical properties. Sodium (Na) and Potassium (K) have the same number of outermost electrons
and are found in group 1. As a result, they have very similar physical and chemical properties.
Group
1A
1
Period
1
8A
18
2A
2
3A
13
1
H
2
Li
3
Na
Mg
12
3B
3
4B
4
5B
5
6B
6
7B
7
8
9
10
1B
11
19
20
21
22
23
24
25
26
27
28
29
4
3
11
K
4
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
7A
17
2
He
6
C
N
O
8
9
F
Ne
2B
12
13
14
15
16
17
18
30
31
32 33
34
35
36
B
Zn
Al
Ga
Si
Ge
7
6A
16
5
8B
Be
4A 5A
14 15
P
As
S
Se
Cl
Br
10
Ar
Kr
The periodic table is divided into three major groups: metals, nonmetals, and metalloids. The
metals are on the left-hand side of the periodic table and the nonmetals are on the right. A zigzag
or stair-step line separates them. Metalloids are adjacent to either side of the stair-step line.
Aluminum, which is a metal, is an exception to this rule.
Atoms combine, or bond, when the positive charge of the proton in the nucleus in one atom is
attracted to the negative electrons of another atom. Since metals have fewer valence electrons,
the attraction between the nucleus and the valence electrons is weaker so the valence electrons
float around the metals instead of being completely attached. This is the controlling factor for the
Octet Rule, which states that elements bond in order to have 0 or 8 valence electrons. In other
words, elements bond to be more stable.
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1
Metals become more stable by getting rid of valence electrons, while nonmetals steal or
share electrons to get to 8 valence electrons. Valence electrons are the controlling factors for
physical and chemical properties of the atoms as listed in the table below.
Properties of Metals and Nonmetals
Property
Metals
Nonmetals
Conducts Electricity
Does Not Conduct
Electricity
Conducts Heat
Does Not Conduct
Heat
Luster
Shiny
Dull
Color
Silver or Gray Color
Earth Tones
Strength
Malleable
Brittle
Reacts with Acids
Does Not React
With Acids
Gives off Electrons
in Chemical
Reactions
Steals Electrons in
Chemical Reactions
Can be Magnetic
(4 types of metals
are magnetic)
Never Magnetic
Conductivity
Reactivity
Magnetism
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Reason
Electricity needs freely
moving electrons to be
conducted.
Heat is the vibration of
the atom. The freely
moving electrons allow the
heat to be passed at a
more rapid rate.
The freely moving
electrons reflect all the
wavelengths of light. The
reflection of all the light
makes metals appear
shiny.
The freely moving
electrons reflect all the
wavelengths of light. The
reflection of all the light
makes metals appear
Silver or Gray
The freely moving
electrons allow metals to
bend instead of break.
Acids want extra
electrons. Metals
electrons float freely
around, and are easy to
steal
The freely moving
electrons around the
nucleus are easy to steal.
Scientists are still not
sure how magnetism
works. They do know that
it involves freely moving
electrons, which metals
have.
2
Part I
Procedure
1. Use the pictures of atoms that are given and a periodic table to answer the questions about
the atoms.
Data Analysis
1.
A. What period is the atom in?
B. What group is the atom in?
C. What is the name of this atom?
D. What other atom would have similar
properties to the atom?
E. Will this atom conduct electricity well?
2.
F. What period is the atom in?
G. What group is the atom in?
H. What is the name of this atom?
I. What other atom would have similar
properties to the atom?
J. Would this atom react with an acid
3.
K. What period is the atom in?
L. What group is the atom in?
M. What is the name of this atom?
N. What other atom would have similar
properties to the atom?
O. Would this atom be malleable or brittle?
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PartII
Materials
Well Plates
Metal Samples
HCl
Alligator Clips with light bulb attached
Procedure
1. Using the periodic table, determine the chemical symbol for each element used. Record on the
data table.
2. Place the 8 test tubes in the test tube rack. Use forceps or a chemical spoon to
place 2 small samples or a few crystals of each element as directed by your teacher.
(Do not touch the elements with your hands!)
3. At your lab station, turn the test tubes upside down and empty the samples onto the
lab sheet within each labeled circle.
4. Observe color, luster, and any unique observable physical properties for each element. (Do not
inhale or taste any substance!) Record observations in the data table.
5. To determine malleability, gently tap the sample element with a small hammer. If the substance
flattens without crumbling, it is malleable. If it crumbles, it is brittle.
6. To test each substance for conductivity, use a battery,
flashlight bulb, copper wire, battery clips, and a battery
holder. Assemble the equipment as indicated in Diagram 1.
Connect the two wires to a piece of each element one at a
time but do not let the two wires touch. Note the intensity
Element
of the light to indicate how well the material conducts
Diagram 1
electricity. If the bulb does not light at all, the element is
not a conductor of electricity.
7. Using a chemical spoon, place one small piece of each element into each test tube.
8. Add 2-3 mL of HCl acid to each test tube. Record all observations in the data table. Watch the
reaction for approximately 5 minutes to observe any changes over time in the elements.
9. Discard the materials as directed by your teacher.
10. Clean the test tubes and return them to the test tube rack.
11. Using a chemical spoon, place one small piece of each element into each test tube.
12. Add 2-3 mL of copper chloride solution to each sample. Record all observations in the data table.
13. Watch the reaction for approximately 5 minutes to observe any changes over time in the element.
14. Wash test tubes and turn upside down to dry.
15. Clean up lab station.
Data Analysis
1. What accounts for the observed differences between element samples?
2. Based on the lab results, fill in the chart below. Justify your reasons for each classification.
Element
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Classification
Justification
4
Metal/Nonmetal/Metalloid
Aluminum
Carbon
Copper
Nickel
Magnesium
Silicon
Sulfur
Zinc
3. Using the periodic table provided, circle all the elements used during the lab. What pattern do
you see between where the element is placed on the periodic table and its properties?
4. Name 2 characteristics you expect the following elements to have based on where they are
located on the periodic table.
CalciumBoronChlorine5. Why do some elements that are classified as metals not look metallic?
6. The light bulb lit when connected to some elements, making a complete circuit. Why would the
bulb not light when connected to other elements even though everything was connected in the
same manner?
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5
Data
Aluminum
Carbon
Copper
Nickel
Magnesium
Silicon
Sulfur
Zinc
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Physical and Chemical Properties of Specific Elements
Element
Chemical
Symbol
Color
Luster
Other Physical
Properties
Malleable or
Brittle
Reaction to
HCl acid
Reaction to
Copper Chloride
Conductivity
Aluminum
Carbon
Copper
Nickel
Magnesium
Silicon
Sulfur
Zinc
Data Table
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