C HAPTER 5 HW P RACTICE
CATEGORIZATION
1.) Sort the following substances into each category.
Ca
H2
NaBr
H 2O
CBr4
O2
C 2H 6O
Ni
Atomic Elements
Molecular Elements
Molecular Compounds
Ionic Compounds
Ni(OH)2
CHEMICAL FORMULAS
2.) Give the chemical formula for each of these nitrogen-oxygen compounds.
=N
=O
Formula
3.) Write the chemical formula for a molecule that contains three carbon atoms, eight hydrogen atoms,
and one oxygen atom. (Note: carbon is written first.)
4.) How many total atoms are present in each compound’s chemical formula?
a. CO2
b. Fe2O3
c. H3PO4
IONIC FORMULAS
5.) When in an ionic compound, give the most common ion formed for each element:
a. Calcium (Ca)
e.
Phosphorous (P)
b. Fluorine (F)
f.
Lithium (Li)
c. Zinc (Zn)
g.
Silver (Ag)
d. Sulfur (S)
h.
Chlorine (Cl)
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6.) Give the chemical formula of the ionic compound formed from each pair of ions.
Ions
Na+ and I–
Mg2+ and Br –
Fe3+ and Cl–
Sm2+ and H–
Formula
7.) When the following pairs of elements form an ionic compound, give what ions they will form, and
the chemical formula for the ionic compound formed.
Elements
Ions of each
Ionic Compound
a. Potassium and Bromine
b. Magnesium and Fluorine
c. Aluminum and Nitrogen
POLYATOMIC IONS
8.) Give the chemical formula of each ionic compound.
2–
1–
Ions
present
ON O
O
Li+
O SO
O O
Na+
1–
1–
OH
Fe2+
OH
Ca2+
Ca2+
Na+
Formula
Ions
present
Cl –
Ba
Cl –
2+
1+
1+
H NH
H H
H NH
H H
2–
OS
O O
Ca2+
3–
3–
OPO
O O
OPO
O O
Formula
9.) How many total atoms are present in each compound’s formula?
b. K2CO3
b. Ca(NO3)2
c. Ba3(PO4)3
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10.) Give the chemical formula of each polyatomic ion.
e. Ammonium ion
e.
Sulfate ion
f. Hydroxide ion
f.
Sulfite ion
g. Nitrate ion
g.
Carbonate ion
h. Nitrite ion
h.
Phosphate ion
11.) Give the chemical formula for the ionic compound formed from each pair of ions.
Ions
Ionic Compound
Ions
Potassium ion + nitrate
Zinc ion + hydroxide
Lithium ion + carbonate
Sodium ion + phosphate
Barium ion + nitrite
Ammonium ion + sulfite
Ionic Compound
DETERMINING CHARGE FROM A FORMULA
12.) From the formula of each ionic compound, determine the charge on each element.
Formula
AlP
NiCl2
PbO2
Fe2S3
Charge on Al:
Charge on Ni:
Charge on Pb:
Charge on F:
Charge on P:
Charge on Cl:
Charge on O:
Charge on S:
13.) Dichromate (Cr2O7) is a polyatomic ion, although not one you should have memorized. Knowing
that sodium dichromate is Na2Cr2O7, what is the formula of aluminum dichromate?
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NAMING IONIC COMPOUNDS
14.) Provide the name for each ionic compound.
Formula
Name
Formula
LiCl
MgS
CaO
BaF2
AlI3
Be3N2
Name
15.) Give the ions present in each ionic compound, then the compound’s chemical formula.
Formula
Ions of each element
Name
Potassium fluoride
Calcium chloride
Sodium oxide
Lithium phosphide
Zinc hydride
Barium oxide
16.) Give the ions present in each ionic compound, then the compound’s chemical formula.
Formula
Ions of each element
Name
Lead(IV) fluoride
Chromium(III) oxide
Copper(II) hydride
17.) Give the ions present in each ionic compound, then the compound’s name.
Formula
Ions of each element
Name
FeCl3
FeCl2
CrO
Cu2S
SnBr4
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18.) Complete the table below.
Formula
Name
Na2O
Formula
Name
BaS
Lithium carbonate
Aluminum bromide
Lead(II) Oxide
Cu3P
FeI3
MgH2
Fe(NO2)2
Ba(OH)2
AgCl
Sn3N2
Ammonium phosphate
Copper(II) sulfate
NAMING MOLECULAR COMPOUNDS
19.) Provide the name or formula for each compound.
Formula
Name
Formula
Carbon monoxide
PF5
SO2
Name
Carbon disulfide
Silicon tetrahydride
N 2O 3
NAMING ACIDS
20.) Provide the name or formula for each acid.
Formula
Name
HCl
Formula
Name
HNO3
Sulfuric acid
H2CO3
HNO2
Acetic acid
Hydrofluoric acid
Phosphoric acid
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SUMMARY PROBLEMS
21.) Which of the following substances match each description ( >1 may fit each description)?
CaBr2
Na2O
N2
HCl
K2CO3
PCl5
Al
Al(OH)3
a. A compound containing twice as many metal atoms as nonmetal atoms.
b. An elemental substance.
c. A molecular substance.
d. An ionic compound containing at least one +2 metal ion.
e. A compound containing three oxygen atoms.
f. An atomic substance.
g. An acidic substance.
22.) Categorize each compound as ionic, molecular or acidic.
Compound
Sodium Sulfate
P 2O 5
HC2H3O2
Sulfur dioxide
Calcium hydride
Ionic (I)
Molecular (M) or
Acid (A)
23.) Provide the name or formula for each of the following compounds.
Formula
Name
Formula
Na2S
Silver sulfate
Copper(I) oxide
Iron(III) iodide
CrBr3
Zn(NO3)2
H3PO4
CCl4
(NH4)2CO3
Ba(OH)2
P 2O 3
Name
Tin(II) nitrite
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