Transcript Ionic bond - EducatorPages.com

Pg. 51
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An ion is an element that has gained or lost
electrons
Oxidation numbers are used to show the
charge of an ion.
A positive ion is called a cation
A negative ion is called an anion
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Write the element symbol first
As a superscript, write the oxidation number
Ex. Ba2+ or Ba+2
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Force that holds oppositely charged ions
together is called an ionic bond
Between a metal and a nonmetal
Electrons are lost or gained
High melting and boiling points
Can dissolve in water to produce electrolytes
(produces an electric current)
Example: NaCl
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Lowest ratio called a formula unit
First write the ions with their oxidation numbers
The charges on each elements switch and
become the subscripts (tells the amount of that
atom) on the other element
Take just the numbers, NOT THE CHARGES
Simplify
The metal goes first then write the nonmetal.
Examples:
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Na and Cl
Mg and F
K and P
Be and O
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Na and Cl
Mg and F
K and P
Be and O
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The cation is written as normal
The anion drops the last part of the element
and add –ide
Example: Sodium + Chlorine = Sodium
Chloride
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Ions made up of more than one element
Charge applies to the entire ion
Written in parenthesis in ionic formulas
Ex. Mg(OH)2
Ion name
Ion Formula
Ammonium
NH4+
Nitrite
NO2-
Nitrate
NO3-
Hydroxide
OH-
Cyanide
CN-
Hypochlorite
ClO-
Chlorite
ClO2-
Chlorate
ClO3-
Perchlorate
ClO4-
Carbonate
CO32-
Sulfite
SO32-
Sulfate
SO42-
Phosphate
PO43-
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Sodium Phosphate
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Calcium Chlorite
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K2CO3
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What is an ionic bond between?
Put the ionic bond together and name it:
◦ Mg and P
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Show the Lewis diagram for the previous
problem
What is a polyatomic ion?
Write the following ionic bond:
◦ Calcium Hydroxide
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Transition metals can have multiple charges
When writing the name, the charge of the
transition metal must go in parenthesis using
Roman numerals
Ag+1, Zn+2, Cd+2 only have one common
charge
Ex. Iron (III) oxide
◦ Cu3P2
◦ MnO