Ionic, Covalent and Metallic Bonding Lab
NAME:___________________________DATE:_____________PERIOD:_______
Background:
Bonding can be ionic, covalent or metallic. An ionic bond occurs when elements of very
different electronegativities combine. This happens when a metal that has a very low
electronegativity comes in contact with a nonmetal that has a very high
electronegativity. Electronegativity is the ability to attract and pull on electrons. The
metal has little ability to pull on the electron while the nonmetal has a high ability to
pull on the electron. Therefore the nonmetal will pull the electron away from the metal
forming an ionic bond!
Ionic Bond: Metal and Nonmetal
Na + Cl  Na+1 + Cl-1
Covalent bonding occurs when elements of similar electronegativity combine. This
happens when nonmetals combine with other nonmetals creating a covalent bond.
Covalent means “sharing” of electrons. If the sharing of the electrons in the bond is
“equal” then a nonpolar covalent bond forms. If the sharing of the electrons in the bond
is “unequal” then a polar covalent bond forms.
Nonpolar Covalent: Diatomic elements!
Electrons are equally shared. Both atoms have the same pull on the electrons.
H● + ●H  H●--●H
Polar Covalent: Two different nonmetals!
Electrons are unequally shared. One atom has a greater pull on the electrons.
C● + ●O  C ●--●O
Metallic bonding occurs in metals. In metals the electrons are not tied to a specific
nucleus so they are free to move creating a model that looks like an array of positive
nuclei surrounded in a sea of electrons. It is important to understand that we use the
term metallic bonding and not metallic bond. The bonding in metals is collective and not
a single bond between one metal atom and another metal atom.
---------------------------------------------+++++++++++++++++++++++
---------------------------------------------Procedure:
Visit each lab station and record the compound formula or element symbol for each
sample. Then decide if the sample represents an ionic compound, covalent compound
or a metal. Then decide the bonding type and bonding description for each sample.
Data:
Sample
Number
Formula
Or
Symbol
Compound
Or
Element
Ionic,
Covalent
or Metallic
Transfer of eSharing of eSea of e-
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Conclusion:
1) ________________ is the atom’s ability to pull or attract electrons.
2) A ______________ bond forms between a metal atom and a nonmetal atom.
3) A ______________ bond forms between two nonmetallic atoms.
4) _________ bonding occurs in metals. The electrons move freely as in a “sea”.
5) A ____________ covalent bond forms when electrons are shared “unfairly”.
6) A ____________ covalent bond forms when electrons are shared “fairly”.
7) Nonpolar covalent bonds always form between ________________ elements.
Teacher Notes: Ionic, Covalent and Metallic Bonding Lab
General Set-up to Create as a kit:
This a very simple lab set up that should be created once then stored as a kit for the
following year. Obtain 20 clear sample bottles with labels. Place the sample number,
formula/symbol and name on each label. I use the polypropylene sample jars sold by
Flinn Scientific.
Sample Number
Formula/Symbol
Name
Iron
1
Fe
2
CO2
Carbon dioxide
3
NaCl
4
Cu
Sodium chloride
Table salt
Copper
5
C12H22O11
6
CuSO4●5H2O
7
Zn
8
MgSO4●7H2O
9
CaCO3
10
NaHCO3
11
O2
12
H2O
13
Al
14
CaCl2
15
Sn
Sucrose
Table sugar
Copper II sulfate pentahydrate
Root killer
Zinc
Epsom’s salt
Bath salts
Calcium carbonate
Tum’s
Sodium bicarbonate
Baking soda
Oxygen gas
Water
Aluminum foil
Calcium chloride
Ice melt
Tin
I strongly suggest that the labels contain all the information on the chart under the set
up notes. This allows students to read “sucrose” then “table sugar”; again trying to
consistently make connections to their everyday surroundings.
This lab is very teacher friendly as it uses household materials that can quickly be
placed into a sample bottle or a test tube with a screw type lid and then placed into a
box for use many years to come.
Teaching Tips:
Students should read the background and answer all of the conclusion questions before
being quietly dismissed to the lab area. This lab takes about 20 minutes to complete
and could serve as an introduction or a review to bond types. It should be noted that
compounds containing polyatomic ions and hydrates have both covalent and ionic
bonding. This can be discussed before the students go to lab or after the students have
done the lab. I use this lab as an introduction to bonding and have the following slide
on the screen when they do the lab. I do not discuss that many compounds have both
types of bonding until after the lab or the next day. The answer key is made according
to using this lab as an introduction. If using this lab for further review then the answer
key should be adjusted to show Sample bottles 6, 9, 10, 17, 19 had both ionic and
covalent bonding.
Ionic
Starts with a metal atom
ends with a nonmetal
atom
Covalent
Starts with a nonmetal
atom ends with a
nonmetal atom
Metallic
You have a metal from
the periodic table
Going Further:
Students could research metallic bonding and why copper is used for household wiring.
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Types of bonding lab