Ionic and Covalent Bonds
Science 10
Ms. Lowrie
Using Lewis Diagrams to Show:
Covalent Bonding
 Steps:
1.
2.
3.
4.
Draw a Lewis diagram for both elements
Determine how to fill valance shell of both by
sharing electrons
Redraw Lewis diagrams together
Circle ‘shared’ electrons
Covalent Examples
a) Hydrogen (H) and Chlorine (Cl)
b) Water = Hydrogen (H) and Oxygen (O)
More Covalent Examples
c) Carbon (C) and Hydrogen (H)
d) Fluorine (F) and Fluorine (F)
e) Phosphorus (P) and Chlorine (Cl)
f)
Carbon (C) and Chlorine (Cl)
Practice: Draw Covalent Bonds
1.
Hydrogen and Hydrogen
2.
Ammonia = Hydrogen and Nitrogen
3.
Chlorine and Chlorine
4.
Nitrogen and Fluorine
5.
Oxygen and Chlorine
6.
Hydrogen and Fluorine
7.
Iodine and Iodine
8.
Carbon and Fluorine
Using Lewis Diagrams to Show:
Ionic Bonding
 Steps:
1.
2.
Draw a Lewis
diagram for
each element
Use arrows to
show how the
electrons move
Example (a):
Potassium (K) and chlorine (Cl)
More Ionic Examples
b) Sodium (Na) and oxygen (O)
c) Calcium (Ca) and chlorine (Cl)
d) Barium (Ba) and fluorine (F)
e) Aluminum (Al) and Oxygen (O)
Practice: Draw Ionic Bonds
1.
Potassium and Phosphorus
2.
Sodium and Fluorine
3.
Aluminum and Chlorine
4.
Potassium and Fluorine
5.
Lithium and Oxygen
6.
Calcium and Phosphorous
7.
Sodium and Nitrogen
8.
Aluminum and Bromine
Writing Chemical Formulas

Crossover Method


Shortcut to writing
ionic compound formulas
Steps:
1.
2.

Determine ions (write cation first)
“Crossover” - Write ion # as subscript (bottom
#) for other element
Notes:

Do not write +1

Write -1 as 
If charges are equal (+2 & -2) = 1 each
Crossover Method – Example
a) Barium and Chlorine
BaCl2
More Crossover Examples
b) Beryllium and Phosphorous
More Crossover Examples
c) Potassium (K) and Phosphorous (P)
d) Sodium (Na) and Fluorine (F)
e) Aluminum (Al) and Oxygen (O)
f)
Potassium (K) and Fluorine (F)
Practice: Crossover Method
1.
Lithium and Oxygen
2.
Calcium and Phosphorous
3.
Calcium and Chlorine
4.
Aluminum and nitrogen
5.
Beryllium and Oxygen
6.
Beryllium and Nitrogen
7.
Potassium and Sulphur
8.
Sodium and Oxygen
Practice Worksheets
1. “Ionic vs. Covalent Bonds”
 Last 2 questions
2. “Write formulas for the following:”
 Using Crossover Method
Polyatomic Ions
 Ions made up of 2+ ions
 “poly” = many
Polyatomic Ion Formulas
 Notes on formula writing:


Use brackets to keep polyatomic ion
“together”
Write cation first
Example
a) Write formula for:
NH41+ and S21.
Draw:
2.
Use Crossover Method:
Examples & Practice
b) Calcium & Nitrate
c) Sodium & Hydroxide
d) Sodium & Sulfate
e) Calcium & Phosphate
f)
Lithium & Hydrogen carbonate
Practice Worksheets
1. “Polyatomic Ion Practice”
2. “Writing Formulas”

No naming yet!
Naming Ionic Compounds
 Steps:
1.
2.
Write cation first
Write anion last with
suffix (ending) “ide”
Potassium Chloride
 Note:

Do not include ‘numbers’!
Naming Ionic Compounds: Examples
a) Ba and Cl
b) Sodium and Fluorine
c) Be and P
d) Ca2+ and Cle) Al3+ and N3f)
Na2O
g) K3P
Naming Ionic Compounds: Practice
1. Be2+ and O2-
Polyatomic Ions:
2. Be2+ and N3-

3. K+ and S2-

Same “ordering” rule!
Don’t change to “ide”
4. Al2O3
1. Ca & NO3
5. KF
2. Na & OH
6. Li2O
3. Na & SO4
7. Ca3P2
4. Ca & PO4
5. Li
& HCO3
Naming Ionic Compounds: Practice
1. “Writing Formulas” worksheet

With names now!
 Complete the following
textbook questions:



#9, 10 (on page 113)
#2 (pg 115)
#4 (on pg 117)
Naming Covalent Compounds
 Steps:
1.
Add numerical prefix (beginning) to both
elements

2.
Ignore ‘mono’ for 1st
element
Add “ide” suffix (ending)
to second element
 Note:

When prefix ending in O or A
is added to oxide, drop last
vowel of prefix
Naming Covalent Compounds:
Examples
1
mono
2
di
3
tri
4
tetra
5
penta
6
hexa
7
hepta
8
octa
9
nona
10
deca
* Second element
in ‘ide’ from
* Drop –a & -o
before ‘oxide’
a) N2S4
dinitrogen tetrasulfide
b) NI3
nitrogen triiodide
c) XeF6
xenon hexafluoride
d) CCl4
carbon tetrachloride
e) P2O5
diphosphorus pentoxide
f) SO3
sulfur trioxide
Naming Covalent Compounds:
Practice
 “Nomenclature – Covalent Compounds”
worksheet
 Complete the following
textbook questions:

#9, 10 (on page 123)