Name: ___________________________
Mods: _______________
Unit Fifteen:
Chemical Bonds
&
Bond Properties
Chemistry: Dr. Wilhelm & Ms. Greendyk
Review Atomic Structure & Electrons
1. Label for atom shown below and fill in the supporting table about atomic structure:
Subatomic particle
Location in the atom
Charge (+,-, neutral)
Proton
Neutron
Electron
Electron Configuration:
Electrons are located outside the nucleus in __________________. Electrons fill the __________
energy orbital (closet to the nucleus) first and then continue by filling the next lowest orbital.
Electrons in the lowest energy level are call ___________________ electrons.
Electrons that have been energized are called _____________________ electrons.
When energized electrons return to the ground state they release energy in the form of __________.
Electron configuration defines how electrons are placed in orbitals.
Elements with a full electron orbital is chemically _______________.
___________________ , in Grp. ________ contain a full orbital of electrons and unreactive.
Valence electrons and periodic trends
_________________ are electrons found at the ________ energy level (orbital) of an atom. Valence
electrons are the electrons that can be shared or transferred to form _____________________.
The organization of the periodic table allows us to recognize valence electrons.
**Flashback- Lewis Dot notation!
Lewis dot notation
describes the valence
electrons for elements in
Groups 1,2, 13, - 18
Fill in the table: Identify the number of valence electrons for the following elements:
Element
Potassium
Bromine
Aluminum
Magnesium
Argon
Symbol
Grp #
# Valence
electrons
Chemical Bonding:
A chemical bond is formed when individual atoms ___________ or ______________ electrons.
When two atoms share electrons they form a ___________________________.
When atoms transfer electrons to form ____________, the attraction of the (+) and (-) ions is called
an ______________________. Compounds have different ________________ depending on if
they are formed from covalent or ionic bonds.
Use the diagram to complete the following sentences:
(word bank) transfer, share, covalent bond, ionic bond
Covalent bonds are formed when atoms ____________ electrons. The sharing of two or
more electrons is called a _________________________ .
Ionic bonds are formed when atoms ______________ electrons to form ________. The
attraction of the ions is called __________ ___________.
Electronegativity
Electronegativity describes and atom’s desire to ____________ electrons. Electronegativity has a
scale of _____ – _________. Atoms with a high electronegativity like to __________ electrons,
atoms with a low electronegativity like to ______________ electrons.
Periodic table and electronegativity:
1. Which element has the greatest electronegativity? ____________
2. Which element have the lowest electronegativity? ____________
3. Looking across the period (row)  does electronegativity increase or decrease? __________
4. Looking down a group (column)  does the electronegativity increase or decrease? _______
5. Elements with a high electronegativity like to gain electrons to form anions.
Write the common ionic state for:
Flourine (F) _____________
Oxygen (O) _____________
Chlorine (Cl) _____________
6. Elements with a low electronegativity like to lose electrons to form cations.
Write the common ionic state for:
Sodium (Na) _____________
Magnesium (Mg) _____________
Potassium (K) _____________
Difference in Electronegativity and Chemical Bonds:
Calculating the difference in ______________helps in identifying the type of _________________ .
Difference in Electronegativity & Bond Type
Non-polar covalent bonds:
0.0 – 0.4
Polar Covalent:
0.5 – 1.8
Ionic Bonds:
1.9 – 3.3
Calculate the difference in electronegativity for the following elements.
Use the chart above to determine if the bond is non-polar covalent, polar covalent or ionic.
Elements
1. Na and Cl
2. C and O
3.
B and F
4.
N and H
5.
K and Br
6.
N and N
Electronegativity
3.16 - .93 = 2.23
Bond Type
Ionic
Ionic – vs- Covalent Bond Property
Ionic bonds are formed between ________________ and ___________________.
Covalent bonds are formed between _____________ and ____________________.
Metals are found on the _________ side of the periodic table.
Non-metals are found on the _________________ side of the periodic table.
Summary of Bond Properties:
Bond Type
Hardness
Melting Point
Solubility
Electrolyte
Ionic
Non-polar
covalent
Polar
Covalent
Review: Naming Ionic and covalent compounds
Formula
MgO
SO3
NaOH
CaCl2
CO2
PF3
Name
Ionic or Covalent?