Chapter Three Review
Name: _________________
1. How is a chemical compound different from an element?
Element
Compound
2. Complete the table regarding the two basic types of compounds.
State the names of the two basic kinds of
compounds.
Ionic
Covalent
Describe how the atoms of the elements
join together for each of the above
compounds.
Give away or take on
electrons to form ions.
Attracted by charge.
Share electrons
Mg+2 mixes with SO4-2. Describe where
each type of bonding occurs.
Between the charge
difference of the metal and
polyatomic ion.
Between the S and O
atoms of the polyatomic
ion.
3. Complete the table by drawing a water molecule. Indicate areas where covalent bonds are
located and then answer the questions.
Diagram
a. Why is the smallest possible sample of water a single water
molecule?
b. Are the atoms in one water molecule covalently bonded to atoms in
neighbouring water molecule? Explain
4. The polyatomic ion dichromate is used in the detection of alcohol on a person’s breath.
How many chromium atoms and how many oxygen atoms are in this ion?
Chromium:
Oxygen:
What is the overall electric charge on the dichromate ion?
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5. Determine whether the compound formed will be ionic or covalent.
Atoms
Ionic or Covalent
Potassium
Sulphur
Ionic
Oxygen
Fluorine
Covalent
Sulphur
Bromine
Covalent
Chlorine
Calcium
Ionic
Copper
Iodine
Ionic
Oxygen
Carbon
Covalent
6. When c o v a l e n t compounds form, two or more n o n - m e t a l atoms react to s h a r e
electrons. When i o n i c compounds form, a m e t a l atom and a n o n - m e t a l atom react
to form ions which are attracted to each other by their o p p o s i t e charges.
7. Distinguish between reactants and products.
Reactants
Products
8. Distinguish between an endothermic change and an exothermic change.
Endothermic Change
Exothermic Change
9. Name the ionic compound that forms when each of the following pairs of elements are
combined chemically.
Elements
Name
Sodium
Iodine
Ionic
Magnesium
Nitrogen
Covalent
Zinc
Oxygen
Covalent
Aluminum
Fluorine
Ionic
Calcium
Bromine
Potassium
Sulphur
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10. Write the name of each of the following compounds.
a. K3N
Potassium Nitride
b. CaS
Calcium Sulphide
c. Ag2S
Silver Sulphide
d. AlP
Aluminum Phosphide
e. Sr3N2
Strontium Nitride
f. Cs2O
Cesium Oxide
g. Mg3P2
Magnesium Phosphide
h. AlF3
Aluminum Fluoride
11. Write the chemical formula for each of the following compounds.
a. Potassium Bromide
KBr
b. Potassium Oxide
K2O
c. Calcium Oxide
CaO
d. Aluminum Oxide
Al2O3
e. Aluminum Chloride
AlCl3
f. Aluminum Sulphide
Al2S3
g. Barium Nitride
Ba3N2
h. Cesium Iodide
CsI
12. Write the name of each of the following compounds.
a. CrCl3
Chromium (III) Chloride
b. CrCl2
Chromium (II) Chloride
c. FeCl2
Iron (II) Chloride
d. Fe2O3
Iron (III) Oxide
e. Au2O
Gold (IV) Oxide
f. Au2O3
Gold (III) Oxide
g. Cu3P2
Copper (II) Phosphide
h. Cu3P
Copper (I) Phosphide
13. Write the chemical formula for each of the following compounds.
a. Iron (II) Fluoride
FeF2
b. Iron (III) Fluoride
FeF3
c. Copper (I) Fluoride
CuF
d. Copper (I) Oxide
Cu2O
e. Copper (II) Oxide
CuO
f. Tin (IV) Oxide
SnO2
g. Nickel (III) Sulphide
Ni2S3
h. Tin (II) Oxide
SnO
14. Why are Roman numerals used when naming compounds?
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15. Write the name of each of the following compounds.
a. (NH4)3P
Ammonium Phosphide
b. (NH4)3PO3
c. (NH4)3PO4
Ammonium Phosphate
d. Na3PO3
Sodium Phosphite
e. Mg3(PO4)2
Magnesium Phosphate
f. FeCO3
Iron (II) Carbonate
Calcium Hydroxide
h. CuOH
Copper (I) Hydroxide
g. Ca(OH)2
Ammonium Phosphite
16. Write the chemical formula for each of the following compounds.
a. Sodium Sulphate
Na2SO4
b. Calcium Nitrate
Ca(NO3)2
c. Aluminum Hydroxide
Al(OH)3
d. Strontium Bisulphate
Sr(HSO4)2
e. Ammonium Bisulphate
NH4HSO4
f. Nickel (III) Chlorate
Ni(ClO4)3
g. Iridium (IV) Nitrite
Ir(NO2)4
h. Calcium Sulphide
CaS
17. Why are brackets used when writing a compound’s chemical formula?
18. Count the number of atoms in each compound.
a. K3P
4
b. Ca3P2
5
c. NaNO3
5
d. Ca3(PO3)2
11
e. Au(NO3)4
17
f. V(CH3COO)5
36
g. NH4HSO4
11
h. (NH4)3PO4
20
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