n.Ionic Nomenclature Day 3 14_15

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NOMENCLATURE
IONIC BONDING
Thursday - Day 3 Notes
Click the link below to watch the video:
VIDEO CLIP ON HOW
ATOMS BOND: IONIC
COMPOUNDS
http://www.nbclearn.com/portal/site/learn/chemistry
-now/how-atoms-bond
Quick Review

_Ions_____ - atoms that have lost or gained one or
more electrons.
__cation___ – positively charged ion
 _____anion___ – negatively charged ion
 The charge on the ion is known as the ___oxidation
number____


__Polyatomic ion____ – ion consisting of two or
more atoms
Practice - write the ion with the charge for the following
elements
* Li
+
* Be
* Al
* Na
*F-
2+
3+
+
2+
* Ca
* Si
+-4
* H
* K
+
+
2-
* O 2-
* Fr +
* N 3-
* Cl -
* P
*S
3-
NOTES #2: Binary Ionic Chemical Names
and Formulas



Ionic bonds are formed between a
metal and a nonmetal OR
cation + anion.
The bond involves the transfer of electrons from the
metal to the nonmetal.
 The electron is transferred from the cation to the
anion so that both atoms have a complete valence
shell (usually 8 electrons in valance).
The overall charge of ionic compounds must equal
zero.
Naming
Ionic Compounds
* First
name the cation and then the anion.
(metal)
(nonmetal)
* Change the ending of the anion to –ide.
Example:
•MgCl2
magnesium chloride
•Li2S
Lithium sulfide
_________________________
Magnesium
oxide
MgO _________________________
K3P
Potassium
phosphide
________________________
CsCl
________________________
Ba3N2
Cesium chloride
Barium nitride
________________________
Practice
DRAWING Lewis Dot Structures for Ionic Compounds
•
•
The overall charge on the compound must equal zero, that is, the number of
electrons lost by one atom must equal the number of electrons gained by the
other atom.
The Lewis Structure (electron dot diagram) of each ion is used to construct the
Lewis Structure (electron dot diagram) for the ionic compound.
The Lewis Dot structures show the location of the valence
electrons after the electrons have been transferred.
Examples: Lithium fluoride
•
Lithium atom loses one electron to form the cation Li+
•
Fluorine atom gains one electron to form the anion F•
Lithium fluoride compound can be represented as
Remember the Octet rule….
DRAWING Lewis Dot Structures for Ionic Compounds
Draw the Lewis structure of Lithium oxide.
formula for this compound?
What would be the chemical
Writing Formulas for Binary
Ionic Compounds
Balance
 When given two ions, __________________
the charges and make them the
subscripts
___________________.
 Do NOT keep the +/- signs
 _______________
Reduce subscripts if possible
This means we must reduce the subscripts if they have a common
denominator.
Example: Ca4F8
CaF2
Writing Formulas for Binary
Ionic Compounds
A. Using Balanced charges Method:
B. Using the Crisscross method:
**Sum of charges must equal zero.
Ex:
a. Na+1 + Cl-1  NaCl
 Example: Li+1 O-2
(+1 + -1 = 0)
b. Mg+2 + O-2  MgO * (+2 + -2 = 0)
* Don’t write this Mg2O2 because it must be
reduced.
Now, let’s use the name to write the chemical formula
Name

Lithium oxide
cation
anion
Li+1
O-2
_______ _______
Li+1
formula
Li2O
_____________
Lewis Dot Structure
Important Facts about Ionic Compounds
• We use subscripts to represent the
number of each ion.
Al2O3
2 Aluminum Ions and 3 Oxide Ions
For example 2…Change it from Magnesium sulfide to Magnesium phosphide
A. Using Balanced charges Method:
Mg2+
Mg2+
Mg2+
6+
and
B. Using the Crisscross method:
Mg2+
P3P3=0
6-
Name
cation

Mg
______
Magnesium phosphide
Mg 3
2+
anion
formula
Mg3P2
P
_______
____________
3-
and
P3S2
Lewis Dot Structure
Homework: Page 9


For added help: watch this video
And use your periodic table!!!!
Notes 3: Binary Ionic Compounds with
Transition Metals (Multivalent cations)

Multivalent Cations are found mostly in
the group B elements. (the middle of
the periodic table)
These elements are also known as the Transition metals.
Roman
Charge
Numeral
If your cation is a transition metal,
then you must specify the charge
with a Roman numeral.
Example: Iron (III) Sulfide
Just like the compounds we looked at
yesterday, the sum of charges must
equal zero . and we can still use the
Criss-cross method when writing the
chemical formula.
I
II
III
IV
V
VI
VII
VIII
+1
+2
+3
+4
+5
+6
+7
+8
Writing & Naming Formulas
with Roman Numerals Practice
Cu+
S2-
Cu2S
Mn2+
O 2-
MnO
Sn4+
F-
SnF4
Lead II iodide
Pb2+
I-
Iron III oxide
Fe3+
O2-
Lead IV oxide
Pb4+
Cobalt III phosphide
Co3+
P3-
Naming Ionic Compounds with
Roman Numerals

If there is a transition metal (B
group element) present in the
formula, you will need to include a
roman numeral when you name the
compound.
So, which metals DO NOT require a
roman numeral?
3+
2+
2+ and Ag+
 Al , Zn , Cd

Writing Multivalent Compounds
HOMEWORK

Complete page 11
REMEMBER:
How can you determine the charge or roman
numeral?
You will have to work backwards.
And
Roman Numeral = Charge of the Metal
Polyatomic Ions

A polyatomic ion are groups of
atoms that behave as one unit.



They are treated like single ions in formulas, but use parenthesis
when more than one is used in a formula.
NEVER change name or look of polyatomic. If you change the
subscripts for any part of the polyatomic, then it is no longer that
same polyatomic ion.
Otherwise….use all the same rules for naming and writing
compounds as with any other Binary Ionic compound.
EX:
NH4+ is not the same as NH+
CO32- is not the same as CO22- or CO2-
Polyatomic Ion Practice
Formula
Al+3
CO3 -2
Al2(CO3)3
Ca+2
NO3 -1
Ca(NO3)2
K+1
ClO3 -1
KClO3
Name
Aluminum carbonate
Calcium nitrate
Potassium chlorate
Question: How would potassium chlorite be different?
K+1
ClO2 -1
KClO2
Name the following compounds
Ba(OH)2
Barium hydroxide
CaSO4
Calcium sulfate
(NH4)3P
Ammonium phosphide
Write the formula for the following
compounds:
cation
anion
formula
Strontium phosphate
2+
Sr
________
_________
______________
Lithium acetate
________
_________
______________
Sodium sulfate
_________
_________
______________
Formula Writing for Compounds
Tips for Success

Before writing any formula,
Identify
Ionic
the type of compound.
 Metal and a Nonmetal or PAI
Molecular  Only Nonmetals
For
all ionic compounds, circle
polyatomic ions.
Examples
iron(III) nitrate I
 carbon tetrachlorideM
 sodium oxide I
 barium hydroxide I
 dinitrogen trioxide M
 ammonium carbonate I
 cobalt(III) nitrite I

Fe(NO3)3
CCl4
Na2O
Ba(OH)2
N2O3
(NH4)2CO3
Co(NO2)3
Naming Ionic Compounds with
Polyatomic Ions


When you name a compound with a
polyatomic ion, the polyatomic ion
keeps its name.
It is easy to identify a compound
with a polyatomic ion because it
will have more than 2 elements
(more than 2 capital letters).
Tips for Success

Before naming ANY compound,
Determine the type of compound.
If the compound is molecular,
remember use prefixes.
If the compound is ionic, answer the
following questions.
Does the metal need a roman
numeral?
Does the compound have a polyatomic
ion?
Examples
NaHCO3 I sodium hydrogen carbonate
I ammonium oxide
 (NH4)2O
 FeSO4 I
iron(II) sulfate
I
 AgC2H3O2 silver acetate
 Ni(NO3)2I
nickel(II) nitrate
 ClO M
chlorine monoxide
I
 AuClO3
gold(I) chlorate

Monday Bell Ringer

Which of the following compounds represent
trichlorine hexoxide?
 A.
Cl3O6
 B. ClO3
 C. O3Cl6

Which of the following compounds represent
manganese (III) oxide?
 A.
MgO
 B. Mn2O3
 C. Mg2O3
Properties of Acids
Corrosive
 Sour Taste
 React with Metals to Produce
Hydrogen Gas (H+)
 pH less than 7
 Can conduct electricity
 Contain H+ ions
 Generally found as (aq) or aqueous

Binary Acids

Binary acids are made up of
HYDROGEN + ANOTHER ELEMENT.
Example:
HCl (hydrogen + chlorine)
Example: H2S (hydrogen + sulfur)
Naming Binary Acids:

1. Prefix: hydro-

2. Element Name

3. –ic

4. Last word: “acid”

Ie: hydroelementic acid
In Class Examples: Naming Binary
Acids

HCl
hydrochloric acid

HF
hydrofluoric acid

HBr
hydrobromic acid
Ternary Acids
These acids contain a
POLYATOMIC ION.
 Also called oxy-acids.
 Example: H2SO3 = sulfurous acid

Naming Ternary Acids


1. Name the polyatomic ion.
2. Change PAI ending in –ate to –ic.
 Example:
sulfate  sulfuric
phosphate  phosphoric

3. Change PAI ending in –ite to –ous.
 Example:

sulfite  sulfurous
phosphite  phosphorous
4. Last word is “acid”.
In Class Examples of Naming Ternary
Acids:

H2 SO4
sulfuric acid

H2 CO3
carbonic acid

HNO2
nitrous acid

H3PO4
phosphoric acid
Writing Acid Formulas
You do not have notes on this- we will practice in
a minute! 
 Always begins with Hydrogen!

 Hydrogen

= H+
You will then follow the same process as you
would an IONIC compound!
hydrochloric acid = H+ and Cl- = HCl
 Example: sulfuric acid = H+ and SO42- = H2SO4
 Example:
Writing Acid Formulas:

Tips:
1. Your first element is ALWAYS H+
2. Identify if it is a BINARY acid or TERNARY acid.
- begins with hydro- and ends in –ic? (1 element!)
- no hydro- prefix, or ends in –ous? (PAI!)
STOP: IN CLASS PRACTICE



I’ll make a SMART board notebook, you will
probably want to do it on the overhead.
Exit Ticket will be the page in the notes titled “In
Class Practice for Nomenclature of Acids.”
Darla just emailed out a homework that I’ll
probably use! 
Writing Formulas for Acids

Remember your patterns.
Hydro-ic
acid  No oxygen
X-ic acid  -ate polyatomic ion
X-ous acid  - ite polyatomic ion
The positive ion is always H+.
 The sum of the charges of the
ions must add up to zero.

Examples

hydroselenic acid
H2Se

phosphoric acid
H3PO4

nitrous acid
HNO2

sulfurous acid
H2SO3

dichromic acid
H2Cr2O7
Keys to Success

Before naming ANY compound,
Identify
the type of compound.
Molecular?
If
Ionic? Acid?
it is molecular, remember to use your
prefixes.
If it is ionic, ask yourself.
Does
the metal need a roman numeral?
Does it contain a polyatomic ion?
If
it is an acid, which pattern does it
follow?
Mixing It Up!
H2CrO4 A
 Na2SO3 I
 HF A
 P5O10 M
I
 Fe(C2H3O2)2
 ZnCl2 I
 H3PO3 A

chromic acid
sodium sulfite
hydrofluoric acid
pentaphosphorus decoxide
iron(II) acetate
zinc chloride
phosphorous acid
Keys to Success

Before writing the formula for ANY
compound,
Identify the type of compound.
Molecular? Ionic? Acid?
If
it is ionic, does it contain a polyatomic
ion?
If
it is an acid, which pattern does it
follow?
No Oxygen?
-ATE Polyatomic Ion?
-ITE Polyatomic Ion?
Examples
barium phosphate I
A -ate
 bromic acid

Ba3(PO4)2
HBrO3

ammonium dichromateI
(NH4)2 Cr2O7

iron(III) sulfide I
Fe2S3

dichlorine heptachlorideM Cl2O7

hydrosulfuric acid A No O H2S

gold(III) chlorate I
Au(ClO3)3
PUZZLE PIECE ACTIVITY ON WRITING
FORMULAS FOR IONIC COMPOUNDS
•Work in pairs to assemble the various compounds.
•Let’s try the first one together.
•What is the compound formed between Mg and F?
Mg2+
Magnesium
Metal
Mg
Metal’s
Charge
+2
Ffluoride
Ffluoride
Nonmetal’s
Nonmetal
Charge
F
-1
A perfectly assembled
compound should be a
square or a rectangle.
Picture of
Puzzle
Pieces
Formula
Name
MgF2
magnesium
fluoride
Sum of
Charges
0
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