NAMES OF SUBSTANCES FROM THEIR FORMULAS
INSTRUCTIONS TO THE STUDENT
The first few items of this set will call to mind material you have already learned. If you
are not sure of these ideas, review them before you continue.
1.
Metals form ions of ________________________ charge, while nonmetals form
(positive/negative)
ions of ________________________ charge.
( positive/negative)
Positive
2.
Negative
Some ions consist of a _______________________ of atoms that act as a unit in
chemical reactions.
Group
3.
The atoms within as ion form covalent bonds with each other by _____________
electrons
Sharing
4.
But the whole group is an ion, and therefore has an electric _________________.
Charge
5.
Groups which are ions are bonded to other ions with _____________________
(covalent/ionic)
bonding.
____________________________________________________________________
Ionic
6.
Formulas are read left to right. In the formula, MgO, the element magnesium if
mentioned before the element oxygen. In all responses to this set, use the name,
not the symbol. For the time being, disregard the subscripts that occur in some
formulas. In CaO, _______________________ is mentioned before oxygen.
1
Calcium
(Check the spelling of each answer. If you misspell a word, write it
correctly several times.)
7.
In the name for the formula NiC12, nickel precedes ______________________.
Chlorine
8.
The formula CaC12 mentions ________________ before _______________.
Calcium
9.
Chlorine
In the name for PbI2, __________________ comes before _________________.
Lead
Iodine
10. __________________ comes before _______________ in the name of the
formula CaS.
____________________________________________________________________
Calcium
Sulfur
11. You now can see that we read names from formulas in the direction of _______
To ____________.
Left
Right
12. The left member of a formula is called
(1) by the name of the single element which appears first in the formula;
(2) by the name of the ammonium ion, NH4+; or
(3) by the special name of the ion if the element that appears first in the
formula can lose varying numbers of electrons.
This third condition will be discussed in a later set.
Let us examine some examples of (1), which states that the left member of a formula
is called by the name of the single element which appears first in the formula.
2
Distinguish carefully between element and atom in this statement. The left member
usually consists of a single element but may contain more than one atom of the
element. NaC1 and NaC2S are both correct formulas. Both have as the left member
the single element ___________________.
Sodium
13. NaC1 is called _________________________ chloride.
_____________________________________________________________________
Sodium
14. Na2S is called ______________________ sulfide.
Sodium
15. KC1 is _______________________ chloride.
_____________________________________________________________________
Potassium
16. K2S is __________________________ sulfide.
_____________________________________________________________________
Potassium
17. The name of A12O3 begins with ___________________________.
_____________________________________________________________________
Aluminum
18. The name for ZnBr2 begins with _____________________.
_____________________________________________________________________
3
Zinc
19. There is only one common positive group, NH4+, called the ammonium ion.
the name for NH4C1 begins with the word “ammonium.” The name for NH4Br
also begins with _________________________.
____________________________________________________________________
Ammonium
20. The name for CaC12 begins with ___________________________.
_____________________________________________________________________
Calcium
21. The name for NH4OH begins with _______________________.
_____________________________________________________________________
Ammonium
22. As you have demonstrated, the left member of a formula is called by the name of
the _____________, or by the name of the NH4+, _________, ion.
_____________________________________________________________________
Element
Ammonium
23. You now know how to name the left member of many compounds. The right
member of a compound may also consist:
(1) of a single element, or
(2) of a negative group.
Note carefully again that single element does not necessarily mean single
atom. The following formulas are all correct: NaC1, CaC12, A1C13. The
right member of each of these formulas is the single element, chlorine.
If the right member of a compound is a single element, change the last part of
the name of the element to –ide.
The right member of the formula NaC1 is the single element chlorine. The
name of the element chlorine is changed to chloride. NaC1 is called sodium
chloride. CaC12 is called ____________ ______________.
_____________________________________________________________________
4
Calcium Chloride
24. CaO is called ______________________- oxide.
Calcium
25. MgO is called ______________ __________________.
Magnesium Oxide
26. CaBr2 is ___________________________.
_____________________________________________________________________
Calcium Bromide
27. CaS is called ____________________________.
____________________________________________________________________
Calcium Sulfide
28.
NaI is ________________________.
_____________________________________________________________________
Sodium Iodide
29. CaC2 is called _______________________________.
_____________________________________________________________________
Calcium Carbide
30. NaF is ______________________.
____________________________________________________________________
Sodium Fluoride
31. ZnO is _______________________.
____________________________________________________________________
5
Zinc Oxide
32. Mg3N2 is called ______________________________.
____________________________________________________________________
Magnesium Nitride
33. Ca3P2 is _______________________________________.
____________________________________________________________________
Calcium Phosphide
34. NH4C1 is called __________________________.
____________________________________________________________________
Ammonium Chloride
35. State the general rule for naming the right member of a formula if it is a single
element . Change the last part of the name of the ___________to _________.
____________________________________________________________________
Element
-Ide
36. Cut out the Reference Table at the back of this book. (If other students will be
using this book, paperclip the table inside the back cover when you have
completed the program.)
The right member of a formula may be a negative group as in KC1O3. Referring
to the table we identify C1O3- as the chlorate ion. KC1O3 is called potassium
chloride. NaC1O3 is called ____________ _______________.
_____________________________________________________________________
Sodium Sulfate
37. Using the table, name the following formulas. CaCO3 is calcium ___________.
_____________________________________________________________________
Carbonate
38. Na2SO4 is _________________________.
6
Sodium Sulfate
39. NaHSO4 is _______________________________.
_____________________________________________________________________
Sodium Hydrogen Sulfate or Sodium Bisulfate
40. Na2SO3 is _______________________________.
____________________________________________________________________
Sodium Sulfite
41. NaHSO3, is ________________________________.
_____________________________________________________________________
Sodium Hydrogen Sulfite or Sodium Bisulfite
42. K3PO4 is ____________________________.
_____________________________________________________________________
Potassium Phosphate
43. KOH is _____________________________.
_____________________________________________________________________
Potassium Hydroxide
44. A1(NO3) is ______________________________.
_____________________________________________________________________
Aluminum Nitrate
45. KNO2; is _____________________________.
_____________________________________________________________________
7
Potassium Nitrite
46. NaC2H3O2 is called _____________________________.
_____________________________________________________________________
Sodium Acetate
47. NaC2H3O2 may also be written CH3COONa. This is an exception to the rule
that the metallic element is written first in the formula. In both cases the
substance is called _____________________.
_____________________________________________________________________
Sodium Acetate
48. The general rule is that if the right member of a formula is a group, the last part
of the name of the compound is the name of that ___________________.
_____________________________________________________________________
Group of Ion
49. You now know how to name a great number of formulas, if you have the table
for reference. Eventually you will want to be able to name them without
depending on the table.
Now open your notebook and return to item 1. Read through the program again,
thinking or saying, but not writing the answers.
Title the page in your notebook Writing Names and Formulas of Compounds.
As you come to a rule or principle, write the rule or principle in your notebook
and under it write one or more examples. For example:
Rule: Formulas are read from left to right.
Example: MgO magnesium before oxygen
CaS calcium before sulfur
When you come a second time to this item, 49, continue on.
Check that you recorded the important rules stated in items 6, 22, 23 or 35, and 48.
You may use examples from the program, or invent your own. It is also wise to
note exceptions as in item 47.
Practice so additional examples.
50. Na3PO4 is ______________________________.
8
Sodium Phosphate
51. KI is __________________________.
_____________________________________________________________________
Potassium Iodide
52. Ca3(PO4)2 is _______________________________.
_____________________________________________________________________
Calcium Phosphate
53. MgCO3 is _______________________________.
_____________________________________________________________________
Magnesium Carbonate
54. Mg(HCO3) is _______________________________.
_____________________________________________________________________
Magnesium Hydrogen Carbonate or Magnesium Bicarbonate
55. NH4F is _____________________________.
_____________________________________________________________________
Ammonium Fluoride
56. Ba(OH)2 is ___________________________________.
______________________________________________________________________
Barium Hydroxide
57. K2SO3 is ____________________________.
______________________________________________________________________
Potassium Sulfite
58. MgSO4 is ___________________________.
9
Magnesium Sulfate
59. A1(C2H3O2)3 is ________________________________.
______________________________________________________________________
Aluminum Acetate
60. The substances you have already named have generally been ionic. Compounds
Are frequently formed by covalent bonding between nonmetals. They are named
from their formulas in the same manner as these ionic substances. For example,
the covalent molecule HC1 is called _______________________.
______________________________________________________________________
Hydrogen Chloride
61. H2S is called ________________________________.
______________________________________________________________________
Hydrogen Sulfide
62. H2O is called ________________________.
Hydrogen Oxide or Water
63. Another compound called by its common, rather than its chemical name, is NH3,
ammonia. NH3 is a compound. Distinguish it carefully from the ammonium ion,
NH4+, a charged particle.
Ammonia is a neutral molecule with the formula _________________.
_____________________________________________________________________
NH3
64. The ammonium ion is a charged particle with the formula ________________.
______________________________________________________________________
10
NH4+
65. Certain elements combine in more than one ratio, for example, CO and CO2. In
order to distinguish these substances from each other, the Greek prefixes
mono- for 1
di- for
2
tri- for
3
tetra- for 4
penta- for 5, etc.
hexa- for 6
are used before the name of the element which occurs in different ratios. CO,
carbon with one oxygen, is called carbon monoxide. The name oxygen changes
to oxide. CO2 carbon with two oxygens, is called carbon dioxide.
In similar fashion, SO2 is called _________________________.
Sulfur Dioxide
66. SO3 (not SO32-) is called _________________________________.
Sulfur Trioxide
67. SO32- is the __________________ ion.
Sulfite
68. CS2 is called ________________________________.
_____________________________________________________________________
Carbon Disulfide
69. PC13 is called ____________________, while PC15 is called _____________.
Phosphorus Trichloride
Phosphorus Pentachloride
70. CC14 is called __________________________.
11
Carbon Tetrachloride
71. If the left-hand member of such a compound also contains more than one atom
Of that element, the left-hand element may also use the numbering prefixes
(mono-, di-, etc.). P2O3 is diphosphorus trioxide. P2O5 is _____________.
_______________________________________________________________________
Diphosphorus Pentoxide
72. The element nitrogen combines in many ratios with oxygen. One of the
compounds is NO2, called by this system ____________________.
______________________________________________________________________
Nitrogen Dioxide
73. N2O5 is called __________________________________.
______________________________________________________________________
Dinitrogen Dioxide
74.
N2O3 is
___________________________.
_______________________________________________________________________
Dinitrogen Trioxide
75. Return to item 60, reread the program, and record in your notebook the rules and
examples for naming certain covalently bonded compounds.
______________________________________________________________________
76. You should have extracted a rule and example from items 60, 65, and 71.
Note also items 63 and 66 which point out common errors. The following items
will give you additional practice in naming compounds. Work carefully. If you
make an error, try to analyze the reason for the error. If you make an error
through lack of understanding, go back over the set for a similar example. If you
were careless, working more slowly will help. You are not working against time.
______________________________________________________________________
77. Zn(OH)2 is ____________________________.
12
Zinc Hydroxide
78. Zn(NO3)2 is _________________________.
Zinc Nitrate
79. Ba(C1O3)2 is _____________________________.
Barium Chloride
80. K2O is _________________________________.
_____________________________________________________________________
Potassium Oxide
81. Na2S is __________________________________.
_____________________________________________________________________
Sodium Sulfate
82. Ca(OH)2 is ____________________________________.
_____________________________________________________________________
Calcium Hydroxide
83. NH4I is ______________________________________.
_____________________________________________________________________
Ammonium Iodide
84. KHSO4 is ____________________________________.
_____________________________________________________________________
Potassium Hydrogen Sulfate or Potassium Bisulfate
85. NaOH is ___________________________________.
_____________________________________________________________________
13
Sodium Hydrogen
86. CaF2 is _______________________________________.
_____________________________________________________________________
Calcium Fluoride
87. HI is ________________________________________.
_____________________________________________________________________
Hydrogen Iodide
88. PBr3 is _____________________________________.
_____________________________________________________________________
Phosphorus Tribromide
89. KMnO4 is __________________________________.
_____________________________________________________________________
Potassium Permanganate
90. ZnCrO4 is ________________________________.
_____________________________________________________________________
Zinc Chromate
14
CHEMICAL FORMULAS FROM NAMES
INSTRUCTIONS TO THE STUDENT
The method is the same as in previous sets. You need a set, and answer sheet, the
Reference Table, a periodic table, a pencil, and a pen and your notebook.
__________________________________________________________________
1. You are now ready to learn how to write the formula of a substance, if you
Are given its name. First, review some ideas you will use during this set.
Metals lose electrons in order to leave a more stable outer shell, often an octet.
Sodium has one electron in its outer shell and loses this electron to form an ion
with a charge of 1+, Na+. Calcium loses 2 electrons to become
__________________.
(symbol with charge)
Ca2+
2.
Nonmetals gain or share electrons to complete an octet in their outer shell.
Chlorine with 7 electrons gains one additional electron to form the chloride
ion with a charge of 1-, C1-. Oxygen with 6 electrons in its outer shell gains 2
electrons to form ____________________________.
(symbol with charge)
O23.
Some ions consist of a group of atoms forming a charged particle. The
carbonate ion is CO32-. From the table determine that the sulfate ion is
____________________.
SO424.
The first rule to formula writing is that the more positive particle comes first.
If a compound is made of sodium and chlorine, Na is written before the C1,
thus: NaC1. In the formula for a compound of oxygen and calcium, the
___________________________ would come first.
(symbol with charge)
15
Ca2+
5.
In the formula for a compound of zinc and iodine ______________________
(symbol with charge)
would come first.
__________________________________________________________________
Zn2+
6.
__________________ comes before ________________ in the formula of a
compound of sulfur and magnesium.
__________________________________________________________________
Mg2+
7.
S2-
The positive particle may also be a group. Referring to the Reference Table,
the common positive group is the ____________ ion, ________________
(name)
(symbol with charge)
__________________________________________________________________
Ammonium
8.
NH4+
In a Compound of chlorine and the ammonium ion, ____________________
(symbol with charge)
would precede _________________________.
(symbol with charge)
__________________________________________________________________
NH4+
C1-
Since the carbonate ion, CO32- is negative, the formula for calcium carbonate
Would place ______________________ before _____________________.
(symbol with charge)
(symbol with charge)
__________________________________________________________________
9.
Ca2+
CO32-
10. Using symbols with their charge, give the order of the particles for the
following compounds. Example: A compound of fluorine and sodium Na+
before F-.
In a compound of zinc and the carbonate ion, _________ before __________.
16
Zn2+
CO32-
11. Potassium and bromine, ________________ before ________________.
K+
Br-
12. Hydroxide and magnesium, ________________ before ________________ .
Mg2+
OH-
13. Particles of _______________ charge come before particles of ___________
charge.
__________________________________________________________________
(+) or Positive
(-) or Negative
14. The second important rule of formula writing is that since compounds are
electrically neutral, the total (+ )charges within the compound must equal the
total (-) charges. The single (+) of Na+ is balanced by the single (-) of C1- so
that the formula for sodium chloride is NaC1. The single (+) for K+ is
balanced by the single (-) for Br-, so the formula for potassium bromide is
________________________ .
__________________________________________________________________
KBr
15. In sodium bromide the __________________ (symbol with charge) balances
the ____________________ (symbol with charge) for bromine and the
formula for sodium bromide is written _____________________.
__________________________________________________________________
Na+
Br-
NaBr
(Remember positive before negative)
16. In sodium iodide, the ________________ (symbol with charge) balances
The _____________________ (symbol with charge) for iodine, and the
formula for sodium iodide is ____________________.
__________________________________________________________________
17
Na+
I-
NaI
17. Now work out the formula for barium chloride from its name. From the
periodic table you deduce that barium loses it 2 outer electrons to form the
ion, ______________________________
(symbol with charge)
__________________________________________________________________
Ba2+
18. One chloride ion has a charge of _____________________, and is written
(number and sign)
____________________________ .
(symbol with charge)
__________________________________________________________________
C1-
1-
19. Since compounds are electrically neutral, 1 Ba2+ ion requires 2 (-) charges
for balance. One chloride ion, C1-, supplies only 1 (-) charge, so
____________________ C1- for balance.
__________________________________________________________________
2
20. Ba2+ balances 2 C1- (2+ balances 2-). Similarly, Ca2+ requires __________
C1- for balance.
__________________________________________________________________
2
21. In barium oxide, 1 Ba2+ balances 1 O2- (2+ balances 2-). In calcium oxide,
1 Ca2+ balances ______________ _________________________.
(number)
(symbol with charge)
__________________________________________________________________
1
O2-
22. In barium sulfide, _______________ Ba2+ balances 1 S2-.
(number)
18
1
23. In magnesium sulfide, ________________ Mg2+ balances ______________
(number)
(number)
2-.
S
_________________________________________________________________
1
1
24. In magnesium oxide, _________________ ________________________
(number)
(symbol with charge)
balances _______________ ________________________ .
(number)
(symbol with charge)
__________________________________________________________________
1
Mg2+
1
O2-
25. In potassium oxide, ________________ ____________________ balances(s)
(number)
(symbol with charge)
______________ _______________________ .
(number)
(symbol with charge)
_________________________________________________________________
2
K+
O2-
1
26. In sodium sulfide, _______________ ___________________ balance(s)
(number)
(symbol with charge)
_____________ _______________________ .
(number)
(symbol with charge)
__________________________________________________________________
2
Na+
1
S2-
27. In aluminum chloride, _________ ___________ balance(s) ___________
____________________ .
__________________________________________________________________
19
1
A13+
3
C1-
28. In aluminum oxide, _____________ _____________ balance(s) __________
__________________ .
__________________________________________________________________
2
A13+
O2-
3
29. In aluminum sulfide, ______________ ________________ balance(s)
_______________ _________________ .
__________________________________________________________________
2
A13+
3
S2-
30. Even is a group is involved in the formula, the compound must still be
electrically neutral. The total charges supplied by the group ions must
balance the total opposite charges. In sodium phosphate, 3Na+ balance PO43-,
or 3+ balance 3-. In sodium carbonate, _________ __________
balance(s) ____________ ______________ .
__________________________________________________________________
2
Na+
1
CO32-
31. In potassium chloride, ____________ _____________ balance(s) ________
_____________________ .
__________________________________________________________________
1
K+
C1O3-
1
32. In calcium hydrogen carbonate, _______________ _____________
balance(s) ________________.
__________________________________________________________________
1
Ca+
2
HCO3-
33. In aluminum hydroxide, ______________ ______________ balances(s)
_________________ _________________.
__________________________________________________________________
20
1
A13+
3
OH-
34. In aluminum chloride, _____________ _____________ balance(s)
________________ _________________ .
__________________________________________________________________
1
NH4+
C1-
1
35. In aluminum hydroxide, _____________ __________ balance(s)
_______________ ________________ .
__________________________________________________________________
1
NH4+
OH-
1
36. In aluminum carbonate, _____________ ____________balance(s)
_________________ ___________________ .
__________________________________________________________________
2
NH4+
CO32-
1
37. Whether the charges are supplied by the atoms or groups, since the
compounds are electrically neutral, the total ___________ ______________
Balances the total ______________ ______________ .
__________________________________________________________________
(+) or Positive charge
(-) or Negative charge
38. Note that the number of times a particle is required depends on both its own
charge, and the charge of the other particle with which it is associated. For
example: In sodium chloride, ___________ (number) Na+ balances 1 C1-,
but in sodium carbonate, __________ (number) Na+ balance 1 CO32-, and in
sodium phosphate, __________ (number) Na+ balance 1 PO43-.
__________________________________________________________________
1
2
3
39. The Na+ ion is required 1, 2, or 3 times respectively, but in every case its
own charge is __________________ .
(number and sign)
21
1+
40. In a given compound, the number of Na+ ions required depends also on the
total ______________ supplied by the negative particle of particles.
__________________________________________________________________
Charge
41. This same principle applies to all other particles, positive or negative. Here
is another example. In sodium chloride, 1 Na+ requires __________ C1(number)
__________________________________________________________________
1
42. But in barium chloride, 1 Ba2+ requires _____________ C1- .
(number)
__________________________________________________________________
2
43. And in aluminum chloride, 1 13+ requires _____________ C1(number)
_________________________________________________________________
3
44. You now know that in writing the formulas for compounds from their names:
(1) The more positive element or group is written first.
(2) The total (+) charges balance the total (-) charges.
(3) The number of times a given particle is required varies from compound t
to compound.
The next rule is that, if a particle is required more than once, the number
indicating how many times a particle is required is written as a subscript
following the symbol for that particle.
If a particle is required only once, omit the subscript.
In sodium chloride, 1 Na+ balances 1 C1- and the formula is NaC1. The
subscript 1 is omitted for both particles. But in sodium carbonate, 2 Na+
balance 1 CO32- and the formula is ____________________ .
__________________________________________________________________
22
Na2CO3
45. In sodium phosphate, ______________ Na+ balance(s) __________ PO43and the formula is ________________ .
__________________________________________________________________
3
1
Na3PO4
46. In barium chloride, ___________ Ba2+ balance(s) ____________ C1- and
the formula is _____________________.
__________________________________________________________________
1
2
BaC12
47. In aluminum chloride, _____________ __________________ balance(s)
(number)
(symbol with charge)
_______________ ___________________ and the formula is ____________ .
(number)
(symbol with charge)
__________________________________________________________________
1
A13+
3
C1-
A1C13
48. Now return to the first item of this set and read through the program again.
In ink in your notebook write the important rules of formula writing and an
example for each rule.
__________________________________________________________________
49. Practice what you have learned by writing the formulas of some compounds.
The following sequence of operations will help you to do it systematically.
Take the time to write out all the steps on scratch paper while you are
learning. It will save you time in the long run. Put only your answer on the
answer sheet, before you check it.
Question: Write the formula for potassium bromide.
Method:
Step I:
Under the name write the symbol of the element each word
represents.
Potassium
Bromide
K
Br
23
49. (continued)
Step II:
Write the charge for each particle.
K+
Br-
Step III: Balance the (+) and (-) charges.
1 K+
1 Br-
Step IV: Write the formula, using subscripts as required, following the
symbol or group.
KBr
Of course you need not recopy each step; merely add new
information. Your scratch work for this equation would look like
this:
Potassium Bromide
1 K+ 1 BrKBr
The key words for each step are I, Symbol; II, Charge; III,
Balance; IV, Formula.
Using a periodic table and the Reference Table, write the formula
for barium oxide.
__________________________________________________________________
BaO
50. Calcium oxide
CaO
51. Barium sulfide
BaS
52. Barium bromide
24
BaBr2
53. Magnesium chloride
MgC12
54. Magnesium sulfide
MgS
If you are making errors, check each step.
I. Correct symbol?
III. Correct balance?
II. Correct charge?
IV. Correct location of subscript?
55. Potassium oxide
K2O
56. Aluminum oxide
A12O3
57. Aluminum sulfide
A12S3
58. If a group ion is required more than once, the ion is enclosed in parentheses
( ) and the subscript follows the parentheses. In aluminum hydroxide, 1 A13+
balances 3 OH-. Its formula is written A1(OH)3. In calcium hydrogen
carbonate, ______________ Ca2+ balance(s) ______________ HCO3-, and
the formula is _____________________________.
__________________________________________________________________
1
.
2
Ca(HCO3)2
59. In calcium hydroxide, _____________ Ca2+ balance(s) _____________OHThe formula is _______________________.
__________________________________________________________________
25
1
2
Ca(OH)2
60. In aluminum chlorate, ____________ A13+ balance(s) __________ C1O3-,
and the formula is ___________________________.
1
3
A1(C1O3)3
61. If the ion is required to be taken only once, both the parentheses ( ) and the
subscript are omitted. Potassium chlorate requires 1 K+ to balance 1 C1O3-.
Its formula is KC1O3. Calcium carbonate requires __________ Ca2+ to
balance ____________ CO32-. The formula for calcium carbonate is
___________ .
__________________________________________________________________
1
1
CaCO3
62. In potassium phosphate, ____________ K+ balance(s) ___________ PO43-,
and the formula is written ___________________ .
__________________________________________________________________
3
1
K3PO4
63. In ammonium chloride, _____________ NH4+ balance(s) ___________C1-.
Since the NH4+ is taken only once, the parentheses ( ) should be omitted.
The formula for ammonium chloride is _________________ .
__________________________________________________________________
1
1
NH4C1
64. In ammonium carbonate, __________ NH4+ balance(s) _________ CO32-.
Since the NH4+ is required _________ times, the parentheses around (NH4+)
must be included. The (CO32-) is required ________ time and the
parentheses around CO32- should be omitted in this formula. The formula for
ammonium carbonate is ______________________ .
__________________________________________________________________
26
2
1
2
1
(NH4)2CO3
65. By similar reasoning and with the aid of the Reference Table and a periodic
table, write the correct formula for the following compounds. The same
method applies:
I, Symbol; II, Charge; III, Balance; IV, Formula, with subscripts and ( ), as
required. Check your answer carefully. All parts must be correct.
(1) symbols
(2) number and location of subscript(s)
(3) presence or absence of ( )
Write the formula for zinc nitrate.
Zn(NO3)2
66. Ammonium hydroxide
NH4OH
67. Calcium chloride
Ca(C1O3)2
68. Potassium nitrite
KNO2
69. Magnesium phosphate
Mg3(PO4)2
70. Barium nitrate
Ba(NO3)2
71. Ammonium phosphate
27
(NH4)3PO4
72. Zinc hydroxide
Zn(OH)2
73. Now, restate the principles and rules upon which formula writing is based.
Rule (1): In formulas the more positively charged particle _____________
the negatively charged particle.
__________________________________________________________________
Precedes or comes before
74. Rule (2): Since compounds are electrically neutral, the total _____________
charges within the compound must balance the total __________ charges.
__________________________________________________________________
(+) or Positive
(-) or Negative
75. Rule (3): A subscript is used to indicate the number of times a particle is
required for balance of charges. The subscript is written ______________
the particle.
__________________________________________________________________
Following or after
76. Rule (4): Group ions are enclosed in ( ) to set them off. If the ion is taken
only once, the ( ) _____________ _____________ . If the ion is taken more
than once, the ( ) must be ___________________.
__________________________________________________________________
Are omitted
Used (or some equivalent word)
77. Now return to item 58 and write in ink in your notebook the rules and
examples for group ions and ( ). You should also copy the method with
examples in item 58, and the checklist for errors in item 65. When you
return to this point, apply these principles to a few more compounds.
__________________________________________________________________
28
78. Barium hydroxide
Ba(OH)2
79. Zinc sulfide
ZnS
80. Magnesium fluoride
MgF2
81. Potassium carbonate
K2CO3
82. Barium hydrogen carbonate
Ba(HCO3)2
83. Ammonium sulfide
(NH4)2S
84. Calcium acetate
Ca(C2H3O2)2
or
Ca(CH3COO)2
85. Magnesium hydroxide
Mg(OH)2
86. Potassium phosphate
29
K3PO4
87. You are now ready to predict the name and formula of certain compounds.
Later you will learn how to predict whether reactions occur between
substances and how to write equations for reactions. Using the principles
you have learned, write the formula and name for a compound of oxygen and
zinc. Which substance is named first in the compound? ________________
__________________________________________________________________
Zinc
88. The formula for the compound is __________________________ .
ZnO
89. Its name is ______________ _________________ .
Zinc oxide
90. The formula and the name of the compound formed between magnesium and
iondine are ______________________ and __________________ .
(formula)
(name)
__________________________________________________________________
MgI2
91. A compound containing the sulfate ion and the barium ion has the formula
____________________ and is named ____________ ____________ .
__________________________________________________________________
BaSO4
Barium sulfate
92. A compound containing the calcium ion and the nitrate ion has the formula
_________________ and is called ____________ ___________ .
__________________________________________________________________
Ca(NO3)2
Calcium nitrate
93. A few substances are called by common names rather than chemical names.
The formula for water is ________________ .
30
H2O
94. NH3 is called _____________________ .
Ammonia
95. Predicting the formulas of covalently bonded compounds is not so simple as
Predicting the formulas of ionic substances. As you study the nonmetals,
you will have a detailed discussion of this problem. However, you should be
able to write the formula if you are given the name. The key is that in the
name, a prefix indicates how many times a particle is required, while in a
formula a subscript following the particle indicates how many times it is
required. For example, the formula for carbon dioxide (carbon with two
oxygens) is written CO2. The di- prefix in dioxide is written as a subscript
following the symbol.
The formula for carbon disulfide is ___________________ .
__________________________________________________________________
CS2
96. The formula for carbon tetrachloride is ____________. Tetra- means “four.”
CC14
97. The formula for phosphorus tribromide is ___________________ .
PBr3
98. The formula for sulfur dioxide is _______________ , while the formula for
Sulfur trioxide is ________________ .
__________________________________________________________________
SO2
SO3
99. The formula for carbon monoxide is ____________________ .
CO
100. Nitrogen dioxide is _______________________ .
31
NO2
101. Diphosphorus pentoxide is _____________________ .
P2O5
102. In oxides, the oxygen is bonded only to the other element. In peroxides, 2
oxygen atoms share a pair of electrons to form an ion. The ion in turn bonds
to another element.
Na
O
Na --- O --- Na
Na
Sodium oxide
Sodium peroxide
The formula for sodium oxide is ___________________ .
Na2O
103. The formula for sodium peroxide is _____________________ .
Na2O2
104. The formula for hydrogen peroxide is ______________________ .
H2O2
105. BaO2 is called ______________, while BaO is called _______________ .
Barium peroxide
Barium oxide
106. If you did not name these compounds correctly, or guessed at the answer,
work through items 106 – 112. Otherwise, go on to item 113. BaO2 has
_____________ positive charges from the barium ion.
__________________________________________________________________
32
2
107. Therefore, the total negative charge must be _______________ .
2
108. This is supplied by O22-, which is the ________________ ion.
Peroxide
109. BaO2 is called _____________________ .
Barium peroxide
110. BaO has _____________ positive charges supplied by the single barium ion.
2
111. The negative charge of 2- (since compounds are electrically neutral) is
supplied by one oxygen, O2-, called the _____________ ion.
__________________________________________________________________
Oxide
112. BaO is therefore called _____________________ .
Barium oxide
113. All compounds which are peroxides end in “O2,” but all compounds ending
in “O2” are not necessarily peroxides. You decide whether the compounds is
an oxide or peroxide on the basis of the previous reasoning. If the “O2” in
the compound represents 2 negative charges, the compound is a _________ .
__________________________________________________________________
Peroxide
114. If the “O2” in the compound represents 4 negative charges (2 X O2-), the
Compound is a(n) _____________________ .
33
Oxide
115. CO2 is called ___________________ .
Carbon dioxide
116. CaO2 is called _____________________ .
Calcium peroxide
You now can write the names and formulas of a great number of substances. The
next set will teach you how to write the formulas and names of substances
containing metals of variable charge.
34
NAMES AND FORMULAS OF COMPOUNDS CONTAINING
ELEMENTS OF VARIABLE CHARGE OR OXIDATION NUMBER
INSTRUCTIONS TO THE STUDENT
Before you begin this set, review from your notebook the principles and examples
of formula writing. This set uses those principles. You need paper, a periodic
table, and the Reference Table of ions.
1.
You have learned that certain metals, the transition elements, can lose varying
numbers of electrons depending upon the chemical conditions. You are not
expected to predict the charge, that is, the numbers of electrons lost, but
should read this information from the periodic table. Refer to the element
copper, on the periodic table. The symbol for copper is ___________ and
its atomic number is _______ .
__________________________________________________________________
Cu
2.
29
Many periodic tables also show the charge or oxidation states of each
element. Check the key to your table and see if this information is given. If
not, your text probably has a list of elements showing variable charge. The
Reference Table of ions at the end of this unit also contains a number of such
elements.
From one of these sources, determine that copper can lose 2 electrons to form
the Cu2+ ion. This particle is known as the copper(II) ion. By similar
reasoning, you can deduce that copper can also lose one electron to form an
ion, Cu+, which is called by this system _______________ .
(name)
Copper(I)
3.
Note that (I) is a Roman numeral, not the symbol for iodine, I. Now apply
the principle of formula writing you have already learned. Copper(II)
chloride has the formula ____________________ .
__________________________________________________________________
CuC12
4.
(Cu2+ balances 2 C1-; subscript follows C1.)
Copper(I) chloride has the formula _________________ .
35
CuC1
5.
Copper(I) oxide has the formula _____________________.
Cu2O
6.
Copper(II) oxide has the formula _____________________ .
CuO
7.
If you are given the formula CuSO4, you must determine whether it is
copper(I) sulfate or copper(II) sulfate. CuSO4 contains the sulfate ion which
has a charge of ____________ . (See Reference Table.)
28.
Since compounds are electrically neutral, CuSO4 must therefore contain
__________________ + charge to balance SO42-.
__________________________________________________________________
2
9.
The formula is CuSO4. This indicates that only one copper particle is
required, so this one particle have all the required charge of ____________ .
__________________________________________________________________
2+
10. The Cu2+ ion is called ______________________________ .
Copper(II)
11. The compound CuSO4 is called __________________________ .
Copper(II) sulfate
12. Using the same reasoning, work out the name for CuNO3. Step I: Determine
the charge of the negative particle. The nitrate ion always has the charge of
__________________ .
36
113. Step II: Calculate the total charge supplied by this kind of negative particle.
CuNO3 contains 1 NO3- group, so the total (-) charge is ____________ .
The total (+) charge is CuNO3 must therefore be ______________ .
__________________________________________________________________
1-
1+
14. Step III: CuNO3 contains ______________ copper particle which supplies
the required 1 + charge. This copper particle is written ________________ .
(symbol with charge)
__________________________________________________________________
1
Cu+
15. Step IV: The Cu+ ion is called ________________________ .
Copper(I)
16. Step V: CuNO3 is called ________________________ .
Copper(I) nitrate
17. the method is summarized here using CuNO3 as an example. Check your
answer.
Step I:
charge of negative particle (NO3-)
Step II:
total negative charge and thus,
Total positive charge [ 1 X (NO3-)]
= 1- and 1+
total positive charge divided by
Number of positive particles
1+
1 Cu particle
= Cu+
Step IV:
name of + particle
copper(I)
Step V:
name of compound
Step III:
= 1-
copper(I) nitrate
37
18. An additional example will be worked out. Name Cu2O and check
your answer.
Step I: charge of negative particle, O2-
19. Step II: total – charge
total + charge
20. Step III: total + charge divided by number of +
Particles (number of particles is deduced
From subscript following symbol Cu2O)
2-
1 X O2 = 2= 2+
2+
2 Cu
= Cu+
21. Step IV: name of + particle
copper(I)
22. Step V: name of compound
copper(I) oxide
23. CuCO3 is called _____________________ .
Copper(II) carbonate
24. CuS is called ________________________ .
Copper(II) sulfide
25. Copper(I) sulfide has the formula _______________________ .
Cu2S
26. CuBr2 is called ____________________________ .
Copper(II) bromide
27. Copper(I) bromide has the formula ________________________ .
38
CuBr
28. Iron is another element that can lose differing numbers of electrons under
Different conditions. From your reference sources, note that iron forms the
ions ___________________________ and _____________________ .
(symbol with charge)
(symbol with charge)
Fe2+
Fe3+
(either order)
29. Iron(II) chloride has the formula _______________________ .
FeC1
30. Iron(III) chloride has the formula ________________________
FeC13
31. Now return to item 1 of this set and read the program again. In your
notebook, add the principles and examples for writing names and formulas
of compounds containing metals of variable charge. Applying these
principles and methods, answer the following questions. If the name of a
compound is given, write the formula. If the formula is given, write the
name using this system of nomenclature.
32. FeSO4 is called ___________________ .
Iron(II) sulfate
33. Fe2O3 is called __________________________ .
Iron(III) oxide
34. Iron(III) nitrate has the formula ____________________ .
Fe(NO3)
35. Iron(II) sulfide has the formula ____________________ .
39
FeS
36. From your reference sources determine that tin forms the ions
_____________________ and _____________________ .
(symbol with charge)
(symbol with charge)
Sn2+
Sn4+
(either order)
37. The formula for tin(II) fluorine is _____________________ .
SnF2
38. The formula for tin(IV) sulfate is ____________________ .
Sn(SO4)2
39. Sn(NO3)4 is called ___________________________ .
Tin(IV) nitrate
40. SnO is called _______________________ .
Tin(II) oxide
41. Lead forms the ions _______________________ and _________________ .
(symbol with charge)
(symbol with charge)
Pb2+
Pb4+
42. Lead(II) acetate has the formula _________________________ .
Pb(C2H3O2)2
or
Pb(CH3COO)2
43. PbC14 is called ______________________ .
40
Lead(IV) chloride
44. PbO is called ____________________________ .
Lead(II) oxide
45. Lead(IV) oxide has the formula ____________________ .
PbO2
46. Work out the name or formula for some additional compounds of this sort.
The formula for chromium(III) oxide is _____________________ .
Cr2O3
47. CrC12
Chromium(II) chloride
48. SbI5
Antimony(V) iodine
49. Antimony(III) sulfate
Sb2(SO4)3
50. Nickel(III) hydroxide
Ni(OH)3
51. Ni(NO3)2
41
Nickel(II) nitrate
52. One of the most common problems is in distinguishing between the two ions
of mercury. The Reference Table indicates that mercury can lose ________
or ____________________ electrons.
1
2
53. Hg2+ is called mercury(II). Mercury(II) chloride has the formula ________.
HgC12
54. Mercury(I) chloride might be expected to have the formula ___________ .
HgC1
55. But an Hg(I) particle is bound covalently with another Hg(I) particle. The
Mercury(I) ion consists of 2 Hg+ particles bonded thus +Hg:Hg+. The
mercury(I) ion is written Hg22+. Mercury(I) chloride requires for balance one
Hg22+ and 2C1- and is written ___________________________ .
Hg2C12
56. The mercury(II) ion consists of one Hg particle with ___________ charges.
2 +
57. The mercury(I) ion consists of _____________ Hg particles each of which
(number)
has _________________ charge.
2
1 +
58. Both the mercury(II) ion, Hg2+, and the mercury(I) ion, Hg22+ have a
charge of ___________________ .
42
2
+
59. Mercury(II) sulfate has the formula ______________________ .
HgSO4
60. If you did not name the last formula correctly, or simply guessed, work
through this item. If you were correct, go on to item 61.
Check your answer here:
Hg2S is called ________________ .
Step I: the charge of the negative
particle is
Step II:
the total – charge is
the total + charge is
Step III: the total + charge is divided
by the number of positive
particles. Number of +
particles is deduced from
the subscript following the
symbol, Hg.
Step IV:
name of + particle
Step V:
name of compound
S2- = 21 X S2 = 22+
2+
2 Hg
= Hg+
mercury(I)
mercury(I) sulfate
61. HgO is called __________________________ .
Mercury(II) oxide
62. The formula for mercury(I) nitrate is _______________________ .
43
Hg2(NO3)2
63. Nomenclature using Roman numerals is not ambiguous. Its use is strongly
recommended by national and international chemical societies. However, an
older system is still used in many books and on labels for reagent bottles.
You may need to be familiar with both systems. The Reference Table for this
unit gives alternate names for ions of metals which have more than one
charge. In your notebook tabulate these ions from the Reference Table under
the following headings. (Iron and copper are filled in as examples.)
Metals that Lose Varying Numbers of Electrons
Element
iron
copper
Ion Ending in –ous
Name
Symbol with Charge
Name
Fe2+
Cu+
ferric
cupric
ferrous
cuprous
Ion Ending in –ic
Symbol with charge
Fe3+
Cu2+
Take sometime ( 5 to 10 minutes if necessary) to study the tabulation. The
purpose of this is to have you discover what the relationship is between the charge
of a particle and the –ous or –ic ending. If you are sure you have discovered the
relationship and have checked that your idea holds true for each elelment on the
tabulation, go on to item 66.
If you have not discovered the relationship after 10 minutes, proceed to the next
line.
64. Do –ous and –ic endings refer to a specific number of charges? See
tabulation.
No. Cu+ is cuprous; Fe2+ is ferrous; Sn2+ is stannous. But Cu2+ is cupric; Fe3+ is
ferric; and Sn4+ is stannic. The –ous and –ic endings do not refer to a specific
number of charges.
65. For a given element, what is true in every case about the relative charge of
the –ous particle as compared to that of the –ic particle?
If you are sure you know, check immediately. If not, go over several
additional examples.
44
You have discovered that in every case for a given element the –ous ending refers
to the particle of lower numerical charge. The –ic ending refers to the particle of
higher charge.
66. Cu+ is lower and is called cupr ___________ ion. Cu2+ is higher and is
called cupr ___________ ion.
Cuprous
Cupric
67. Fe3+ is called the ferr ________ ion. Fe2+ is called the ferr ________ ion.
Ferric
Ferrous
68. A helpful memory device is that –ous and lower both contain the letter “o.”
-ic and higher both contain the letter “i.” CuC12 is called copper(II) chloride
or _________________ .
Cupric chloride
69. CuBr is called copper(I) bromide or ________________ .
Cuprous bromide
70. Give two names for the following compounds. FeO is _____________ or
_____________________ .
Iron(II) oxide
Ferrous oxide
71. SnF4 is ___________________ or _________________ .
Tin(IV) fluoride
Stannic fluoride
72. Pb(NO3)2 is _________________ or _________________ .
Lead(II) nitrate
Plumbous nitrate
73. Sb3+ is called antimony(III) and also the _______________ ion.
45
Antimonous
74. By the same reasoning that you used previously, you should be able to write
The formula from a name of a compound containing –ous or –ic forms. Write
the formula for cupric sulfate. From a reference source, determine that copper
forms an ion of ______________________ charge and another of
(number and sign)
_____________________
(number and sign)
1+
2+
(either order)
75. Cupric sulfate requires the particle of ____________________ charge.
(lower/higher)
Higher
76. The copper particle of higher charge is _____________________________ .
(symbol with number and sign)
Cu2+
77. Cupric sulfate requires _______________ SO42- to balance Cu2+
.
(number)
1
78. The formula for cupric sulfate is _____________________ .
CuSO4
79. Ferric nitrate has the formula ________________________ .
Fe(NO3)3
80. Ferrous sulfate has the formula ______________________ .
46
FeSO4
81. Another name for ferrous sulfate in the system using Roman numerals is
_____________________ .
Iron(II) sulfate
82. Chromic hydroxide has the formula ____________________ .
Cr(OH)3
83. Mercuric nitrate has the formula _________________________ .
Hg(NO3)2
84. Hg2C12 can be called mercury(I) chloride or ________________ .
Mercurous chloride
85. HgO is mercur __________________ oxide.
Ic
In your notebook, following your tabulation of –ous and –ic ions, write a
statement in your own words about the relationship between charge and the –ous
and –ic endings. Select some illustrative examples from items 67 to 85, or better
still, write some examples of your own.
There is one other method of naming compounds that needs to be reviewed at this
time. It is the system using the prefixes mono-, di-, tri-, etc., to indicate how
many times a particle is required.
It is therefore possible to name one compound three different ways. SbC13 can be
called antimony(III) chloride
antimonous chloride
antimony trichloride
86. SbCI5 can be called by three names (in any order): ________________ or
______________________, or _______________________ .
47
Antimony(V) chloride, Antimonic chloride, Antimony pentachloride
87. CaF2 is called ___________________________ .
Calcium fluoride (It would not be incorrect to call it calcium difluoride, but it is
not necessary since calcium has only one ion, Ca2+, and only one calcium fluoride
compound exists.)
88. The preferred name of MgO is ______________________ .
Magnesium oxide (not magnesium monoxide)
More experience in chemistry will help you select the best name. Some names
are preferred by custom. This program has not taught you all the possible ions,
nor all the metals of variable charge. If you have mastered this unit, you have a
good background for equation writing and chemical calculations.
Your teacher will tell you whether you need to memorize the names, symbols, and
charges of the common ions and when you will be tested on this material. The
most frequent source of trouble in chemistry is in formula writing. Master it now.
48
NAMES AND FORMULAS OF INORGANIC ACIDS AND THEIR
SALTS
INSTRUCTIONS TO THE STUDENT
This set will help you learn how to name an acid or salt if you are given its
formula, and how to write the formula from the name of an inorganic acid or salt.
This set is not concerned with theories of acid formation nor with definitions of
“acid” and “salt.” Here you will learn names and formulas. Work through this
set in the usual manner. You will need a periodic table and later, your notebook.
One of the problems in naming acids is there is no difference in the written
formulas for certain covalently bonded substances and the acids they form in an
ionizing solvent, usually water.
1.
For example, the formula HC1 stands for the gas, hydrogen chloride, and also
for hydrochloride acid. H2S stands for both hydrosulfuric acid and for the
gas, __________________________ .
Hydrogen sulfide
2.
In this discussion, a formula such as H2SO4 will always refer to the acid
called _________________ .
Sulfuric acid
3.
Your experience in formula writing has taught you that HNO3 is the formula
for _____________ acid and the salts of this acid are called ___________ .
Nitric
4.
Nitrates
HC1 is the formula for ______________ acid. It is called ______________ .
Hydrochloric
5.
Chlorides
Formula
Name of Acid
Name of Salt
HNO3
HC1
Nitric
Hydrochloric
Nitrates
Chlorides
49
Why are there differences in names? Acids are divided into two groups on the
basis of number of elements which they contain. These groups are the binary
acids and the ternary acids. Ternary acids contain three elements; binary acids
contain ________________ elements.
Two
6.
HNO3 is a _____________ acid. HC1 is a _______________ acid.
(binary/ternary)
(binary/ternary)
Ternary
Binary
7. H2S is a _______________ acid. H2SO4 is a _____________ acid.
__________________________________________________________________
Binary
Ternary
8. HC1, HBr, H2S are all _____________ acids. These acids contain two
elements; one of the elements in every binary acid is always the element
__________________ .
Binary
Hydrogen
9. The names of binary acids specify both the hydrogen and the other element.
HC1 is called hydrochloric acid; hydro- for the hydrogen, chlor- for the
chlorine, ic for the group ending. HF is called _______________ acid.
Hydrofluoric
10. H2S is called ___________________ acid.
Hydrosulfuric
11. By the reverse reasoning, if the name of an acid begins in hydro- and ends in –
ic, you know that it must be a _____________________ acid.
(binary/ternary)
50
Binary
12. Hydrobromic acid is a binary acid containing the elements
__________________ and ____________________ .
(name and symbol)
(name and symbol)
Hydrogen
H
Bromine
Br
13. By the rule of formula writing which you learned earlier, the formula of
hydrobromic acid is __________________ .
HBr
14. Hydriodic acid (note spelling) has the formula __________________ .
HI
15. You can even apply these rules to exotic compounds you have never heard of.
Selenium, Se, atomic number 34, forms an acid called hydroselenic acid.
Locate the element on your periodic table and write its formula. The formula
for hydrodelenic acid is __________________________ .
H2Se
16. Let us now consider the names of salts of binary acids. Salts of binary acids
end in –ide. The salts of hydrochloric acid drop the hydro- and end in –ide.
They are called __________________ .
Chlorides
17. The slats of the acid HBr, _______________, are called _______________ .
(name)
Hydrobromic acid
Bromides
18. The salts of HI, __________________, are called ________________ .
(name)
51
Hydrosulfuric acid
Iodides
19. The salts of H2S, ______________, are either sulfides or hydrogen sulfides.
Hydrosulfuric acid
20. H2S can form two ions, HS- and S2-. Salts with HS- are called hydrogen
sulfides, since the ion contains hydrogen. Salts with S2- contain no hydrogen
and are simply called ___________________ .
Sulfides
21. Na2S is called _________________ NaHS is __________________ .
Sodium sulfide
Sodium hydrogen sulfide
22. The formula for potassium hydrogen sulfide is __________________ .
KHS
23. KHS is formed from the acid, ____________, whose formula is _________ .
(name)
Hydrosulfuric
H2S
24. The formula for zinc sulfide is ______________________ .
ZnS
25. ZnS is formed from the acid, _____________, whose formula is _________ .
(name)
Hydrosulfuris
H2S
26. You have just reasoned that if the second part of the name of a salt contains
The name of a n element and ends in –ide, the salt must be that of a
_________________________ acid.
(binary/ternary)
52
Binary
27. Apply the rules to the following questions. NaF is called ______________ .
The acid from which it is formed is named ___________________ and has
formula _________________ .
Sodium fluoride
Hydrofluoric acid
HF
28. Potassium selenide has the formula _______________ . It is formed from
The acid whose formula is __________ and whose name is _____________ .
K2Se
H2Se
Hydroselenic acid
29. Now go back to the beginning of this set and work through the program
again, writing in your notebook the important rules and examples. When you
return to this point, work out the next few examples.
The zinc salt of hydrobromic acid has the formula _____________ and is
called ________________ .
ZnBr2
Zinc bromide
30. NH4I is the ammonium salt of the acid, ___________, ______________ .
(name)
(formula)
Hydriodic acid
HI
31. A magnesium salt of hydrosulfuric acid has the formula __________ and is
called ____________________ .
MgS
Magnesium sulfide
or
Mg(HS)2
magnesium Hydrogen
32. A1C13 is the aluminum salt of the acid, ____________, _____________ .
(name)
(formula)
53
Hydrochloric acid
HC1
33. If you missed any of the last four items, you need to review this set again,
review the earlier sets on formula writing, or work more carefully. Let us now
consider the ternary acids and their salts. All ternary acids contain
_______________________ elements.
(how many)
Three
34. HNO3, H2SO4, H2SO3 are all ternary acids. Two of the three elements in
any ternary acid are always _________________ and _______________ .
Hydrogen
Oxygen
(either order)
35. Since all ternary acids contain oxygen, these acids are also called oxy- acids.
H2S is the binary acid of sulfur; H2So4 is an oxyacid. H2SO4 is also called a
______________ acid.
(name)
Ternary
36. A particular element may form several different oxyacids depending upon its
oxidation state. Chlorine is such an element. It forms HC1O, HC1O2,
HC1O3, and HC1O4. There is a specific name for each of these acids. In each
of the oxyacids of chlorine, there is (are) ________ atom(s) of hydrogen.
One
37. In each case the charge on the negative ion (C1O-, etc.) is _____________.
(Refer to item 36.)
1-
(to balance the H+)
38. In each case of the oxyacids of chlorine, there is (are) __________ atom(s)
of chlorine. (Refer to item 36.)
54
One
39. The difference between the oxyacids of chlorine is therefore in the ________
of _______________ atoms. (Refer to item 36.)
Number
Oxygen
40. There is also a difference in the oxidation state of chlorine. For each element
-chlorine, bromine, sulfur, phosphorus, etc.-which forms several oxyacids,
you will need to memorize the name and formula of the “fundamental acid.”
For the chlorine group, the fundamental acid is HC1O3, called chloric acid.
The formula for chloric acid is ________________ .
HC1O3
41. You recognize the C1O3- group as the ___________________ ion.
Chlorate
42. The salts of chloric acid, ______________, are called ______________ .
(formula)
HC1O3
Chlorates
43. The salts of hydrochloric acid, ______________, are called ____________ .
(formula)
HC1
Chlorides
44. Ternary acids contain H, O, and a third element. The fundamental oxyacid
of an element is named from the root for the third element plus –ic. HC1O3 is
chloric acid. The salts of the fundamental acid end in –ate. The salts of
chloric acid are ___________________ .
55
Chlorates
45. H2O4 is the fundamental oxyacid for sulfur. H2SO4 is called __________ .
Its salts are called ________________ .
(name)
Sulfuric acid
Sulfates
46. The fundamental oxyacid of nitrogen is HNO3. HNO3 is called _________ .
Its salts are called ___________________ .
(name)
Nitric acid
Nitrates
47. The name of a fundamental acid ends in __________ and the name of its
salt ends in _______________ .
-ic
-ate
48. Return now to distinguishing among the oxyacids of chlorine. They are:
Formula
HC1O4
HC1O3
HC1O2
HC1O
Name of Acid
Name of Salt
Chloric
Chlorate
You call that if an ion has two oxidation states, the name of the ion of higher
oxidation state in –ic; the name of the ion of lower oxidation state ends in
- ous.
HC1O3 is chloric acid. HC1O2 with one less oxygen atom and a lower
oxidation state is thus called chlor _________ acid.
Chlorous
49. HC1O3, _____________ acid, produces ___________________ .
(name)
(name of salt)
HC1O2, _____________ acid, produces chlorites.
(name)
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Chloric
Chlorates
Chlorous
50. Chlorous acid, _______________, produces salts called ___________ .
(formula)
(name)
________________ .
(ion)
HC1O3
Chlorates
C1O3-
51. Chlorous acid, ______________, produces salts called ______________ .
(formula)
(name)
______________ .
(ion)
HC1O2
Chlorites
C1O2-
52. By similar reasoning, the fundamental acid of nitrogen is HNO3. It is called
_______________ and its salts are ______________, ________________ .
(name)
(ion)
Nitric acid
Nitrates
NO3-
53. The formula of nitrous acid is ________________ . It salts are __________,
(name)
_______________ .
(ion)
HNO2
Nitrates
NO2-
54. H2SO3 is called __________ acid. Its salts are called _______________ .
Sulfurous
Sulfites
55. Now go back and look at item 48. Notice HC1O. This oxyacid has one less
oxygen than HC1O2 and an even lower oxidation state. The Greek prefix
hypo- means “below” of “under,” as in hypodermic, “under the skin.” HC1O2
is chlorous acid. HC1O which is lower is called hypochlorous acid. Its salts
are called hypochlor ________________ .
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Hypochlorites
56. HBrO3 is called bromic acid. HBrO is called ____________ . Its salts
are called ________________, _______________ .
(name)
(ion)
Hypobromous acid
Hypobromites
BrO-
57. H3PO4 is the fundamental acid for phosphorus. H3PO4 is called _________
acid.
Phosphoric
58. Hypophosphorous acid has the formula _______________ . Its salts are
called ___________________, __________________ .
(name)
(ion)
H3PO2
(2 less O than H3PO4)
Hypophosphites
PO23-
59. Mg(BrO)2 is called __________________ .
Magnesium hypobromite
60. Refer again to item 48. Note the acid HC1O4. This has one more oxygen, a
higher oxidation number, than the fundamental acid HC1O3. The prefix permeans “over” or “higher.” Since HC1O3 is called chloric acid, HC1O4, which
is higher, is called __________________ chloric acid.
Per61. If the salts of chloric acid are called chlorates, you would expect the salts of
perchloric acid to be called ___________________ .
Perchlorates
62. HbrO4 is called _______________, its salts are ___________, __________ .
(name)
(ion)
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Perbromic acid
Perbromates
BrO4-
Return now to item 34. In your notebook write the title, Naming Ternary Acids
and Their Salts. When you come to item 48, copy in your notebook the tabular
form. Complete the tabular form as you work through the rest of the program.
When you return to this point copy in your notebook this list of Names and
Formulas of Common Fundamental Acids: HNO3, nitric acid; H2SO4, sulfuric
acid; H2CO3, carbonic acid; H3PO4, phosphoric acid; HbrO3, bromic acid; HIO3,
iodic acid; HC1O3, chloric acid; HFO3, fluoric acid. Note that all the halogen
ternary acids are of the form HXO3. If you know one, you know them all.
63. There is one further point about those ternary acids which form more than
one ion. To review: in the binary acids, H2S, ___________, formed two ions,
(name)
HS-, _______________, and S2-, ________________ .
(name)
(name)
Hydrosulfuric acid
Hydrogen sulfide
Sulfide
64. Among the ternary acids, H2SO4 forms two ions, HSO4- and SO42-. HSO4is called the hydrogen sulfate ion. SO42- is called the _____________ ion.
(name)
Sulfate
65. K2SO4 is named ______________ . KHSO4 is named ______________ .
Potassium sulfate
Potassium hydrogen sulfate
66. NaHCO3 is called ________________ . Na2CO3 is called _____________ .
Sodium hydrogen carbonate
Sodium carbonate
67. Calcium sulfite has the formula _________________ . Calcium hydrogen
sulfite has the formula _____________________ .
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CaSO3
Ca(HSO3)2
68. H3PO4 forms three different ions – H2PO4-, HPO42-, PO43-. H2PO4is called dihydrogen phosphate; HPO42- is called ______________; and PO43is called ________________.
Hydrogen phosphate
Phosphate
69. HPO32- is called ________________; H2PO3- is called _______________ .
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