Ionic Compounds
Compounds formed between a Metal and a Non-Metal ion.
To achieve a stable valence shell (8 max) elements want _____________________________. They do this by reacting
chemically with other unstable elements to form a ________________. In the case where a metal and a non-metal
react, the ____________________and transfers it onto the ___________ (who wants to gain valence electrons). By
doing this both end up with full valence shells, both are stable and happy and a very special type of chemical bond is
formed – the_________________
ionic bond-______________________________________________________________. When a metal_________
valence electrons it becomes _________________________. When a non-metal _________ valence electrons, is
becomes ___________________. Therefore an ionic bond is a chemical bond where a positively charged metal ion is
bound to a negatively charged non-metal ion. What do we know about opposite charges?
Lets show this bond using a B-R diagram:
How are ionic compounds found in nature?
Properties: They are 3-dimensiona,l brittle crystal solids that have very high melting and boiling points. They _________
very well in water and they can __________________ when put in water. When they dissolve in water, they separate
back into their ions. All salts are examples of ___________________________________.
*Remember an ionic bond is just two oppositely charged ions attracting each other. One is a metal, one a non-metal.
Anatomy of a Chemical Formula
Chemical Formula: a combination of symbols and subscripts that represent the ratio of elements in a compound.
Chemical Symbol:
Identifies which
___________ are
present
Na3N
Subscript: Identifies the
number of ____________
present.*represents the atom
immediately left.*
Naming Simple Ionic Compounds.
The name of the first element (most metallic) is unchanged.
The ending of the second element is changed to “ide”
e.g. Na3N is sodium nitride
KCl
MgO
LiF
CaI2
Na3N
BeS
Writing Formulas for Simple Ionic Compounds
To determine the chemical formula of a compound the number of atoms of each element is found using ion charges. We
will use what is know as the criss-cross rule. (only for ionic compounds)
e.g.
Potassium's ion has a charge of 1+ and sulphur's ion has a charge of 2-, (Group IA and VIA of the periodic table).
(You must always figure out what each ions charge is before writing the formula)
B-R
K1+
Sodium fluoride
Lithium oxide
Aluminium nitride
S2-
Calcium bromide
Magnesium nitride
→
K2S
Hydrogen sulfide
Potassium phosphide
Naming Ionic Compounds for transition metals with non-metals (Multiple Positive Charges)
* Reminder:
Ionic Compounds are when a metal ion and non-metal ion combine
Naming: keep metal name unchanged and change non-metal ending to "ide"
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Atoms with more than one Positive Charge (The Transition Metals)
Some metals located in groups 3-12 are known as the transition metals and they can have more than one
ion per element.
These atoms are Multivalent, meaning they can have more than one positive charge.
Some Common Multivalent atoms:
Name of Element
Symbol
Copper
Cu
Iron
Fe
Lead
Pb
Tin
Sn
Nickel
Ni
Cobalt
Co
Gold
Au
Ionic Charge
+1 or +2
+2 or +3
+2 or +4
+2 or +4
+2 or +3
+2 or +3
+1 or +3
Roman #
I, II
II, III
II, IV
II, IV
II, III
II, III
I, III
Negative ions only have one charge per atom.
Naming Multivalent Ionic Compounds- A roman numeral must be included in the name of the metal to indicate which
ion was used to make the compound.

It is important to remember which elements are multivalent so you can name them accordingly



The name of the first element (most metallic) is unchanged. Reverse the criss-cross rule to put back the charges
Be careful; the subscripts of some compounds have been reduced!
Now name the metal using roman numerals and write the non-metal with the ending "ide"
Ex. Fe2O3
1. Fe is a multivalent transition metal
2. Fe3+ O23. Double check to make sure the numbers haven't been reduced
4. Iron III oxide
Ex. CuO
1.
2.
3.
4.
Writing Formulas for Multivalent ionic Compounds
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

A roman numeral is included in the name to indicate what metal ion was used
The roman numeral is now the new ionic charge (# of electrons that were removed from the atom to make the ion)
Use the criss-cross rule
ex. Copper II Chloride
Nickel III sulfide