5.8 Ioni Compounds
May 23­11:17 AM
5.8 Ionic Compounds
Feb 15­5:06 PM
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5.8 Ioni Compounds
Formation of Ions from Metals
• Ionic compounds result when metals react with nonmetals • Metals lose electrons to match the number of valence electrons of their nearest noble gas
• Positive ions form when the number of electrons are less than the number of protons Group 1 metals → ion 1+
Group 2 metals → ion 2+
Group 13 metals → ion 3+
Dec 9­9:20 PM
Ionic compounds are basically defined as being compounds where
two or more ions are held next to each other by electrical
attraction.
One of the ions has a positive charge (called a "cation"). Cations
are usually metal atoms.
The other has a negative charge ("anion"). Anions are either
nonmetals or polyatomic ions (ions with more than one atom).
Feb 15­5:08 PM
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5.8 Ioni Compounds
How to Name an Ionic Compound
1) Place the positive ion (cation) name first.
2) Place the negative ion (anion) name last.
3) Drop the ending in the name of the anion and replace
with an -ide.
Example: sodium chloride
cation + anion with -ide ending
Apr 11­8:23 AM
How to Create a Formula
1) Write the symbol for the metal cation, indicating the
positive charge by determining how many valence electrons it
will lose.
Example: Sodium has 1 valence electron. It will lose this
electron to become a sodium ion with a 1+ charge. It is
written as Na 1+.
2) Write the symbol for the nonmetal anion, indicating the
negative charge by determining how many valence electrons
it will gain.
Example: Chlorine has 7 valence electrons. It will gain one
more valence electron to become a chloride ion with a 1charge. It is written as Cl 1-.
Apr 11­8:21 AM
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5.8 Ioni Compounds
3) Check to see if your positive charge and negative charge
balance. If they do not balance, you will need more than one
cation or anion. Determine how many cations and anions you
will need to balance the charge on the compound.
Example: Na 1+ and Cl 1- balance. Only one cation and one
anion are needed.
4) Write the symbol for the cation, followed by the symbol
for the anion. If you have determined that you need more
than one cation or anion to balance the compound, write the
number of cations or anions you need as a subscript to the
right of the ion. If you only need one, there is no need to
write the number 1.
Apr 11­8:22 AM
Naming Ionic Compounds Practice Worksheet
Feb 15­5:17 PM
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5.8 Ioni Compounds
Name the following ionic compounds:
1)
NH4Cl _____________________________________
2)
Fe(NO3)3 _____________________________________
3)
TiBr3 _____________________________________
4)
Cu3P _____________________________________
5)
SnSe2 _____________________________________
6)
GaAs _____________________________________
7)
Pb(SO4)2 _____________________________________
8)
Be(HCO3)2 _____________________________________
9)
Mn2(SO3)3 _____________________________________
10) Al(CN)3 _____________________________________
Feb 15­5:17 PM
Write the formulas for the following compounds:
11)
chromium (VI) phosphate _____________________________________
12)
vanadium (IV) carbonate _____________________________________
13)
tin (II) nitrite _____________________________________
14)
cobalt (III) oxide _____________________________________
15)
titanium (II) acetate _____________________________________
16)
vanadium (V) sulfide _____________________________________
17)
chromium (III) hydroxide _____________________________________
18)
lithium iodide_____________________________________
19)
lead (II) nitride _____________________________________
20
silver bromide _____________________________________
Feb 15­5:17 PM
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5.8 Ioni Compounds
Transition Metals
Transition metals are like most other metals because they have atoms that become “more stable” by losing their electrons and forming positive ions. However, they are different than many metals because transition metals can become stable by losing different numbers of electrons, depending upon the reaction conditions and how many valence electrons they lose. This means they can form more than one kind of ion!!
Example: Copper can lose one electron to form an ion with a single charge known as Cu1+ or copper (I). Copper can also lose two electrons to form an ion with a double charge known as Cu2+ or copper (II).
Apr 12­12:46 PM
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