Ionic and Covalent Bonding
Goals: Students will explain the difference between ionic, covalent and polar covalent bonding in terms of
electronegativity and electron configuration.
The Plan:
Part A: Reading
Students will read silently to themselves and then listen as the teacher reads it aloud.
Part B: Vocabulary
-
Students will highlight chemistry related vocabulary words that they know and define them on the Tchart provided.
They will then pair up with and share their list, writing down anything that their neighbor got but they
didn’t.
Students will then highlight context-based vocabulary individually (both ‘nerd terms’ and regular
terms) in a different color and attempts to define the words based on the context in the reading.
Pair with a neighbor and create a complete vocabulary list for both of the students
Create a list of terms as a class
Part C: Analysis
-
Students will receive the reading guide with questions and in small groups work on analyzing the text
one question at a time, using the text and prior knowledge to answer them.
When the groups are done, we will discuss the analysis as a class.
Repeat for each paragraph
Part D: Writing
Students will be given a writing prompt on which to write an essay. They are given the steps to follow for this
process which includes brainstorming, outlining, rough draft with edits and a final draft.
Name:_____________________________
Bonding Reading and Writing
Article: http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/bond.html
Chemical Bonding
Chemical compounds are formed by the joining of two or more atoms. A stable compound occurs when the total energy
of the combination has lower energy than the separated atoms. The bound state implies a net attractive force between
the atoms ... a chemical bond. The two extreme cases of chemical bonds are:
Covalent bond: bond in which one or more pairs of electrons are shared by two atoms.
Ionic bond: bond in which one or more electrons from one atom are removed and attached to another atom, resulting in
positive and negative ions which attract each other.
Covalent Bonds
Covalent chemical bonds involve the sharing of a pair of valence
electrons by two atoms, in contrast to the transfer of electrons in
ionic bonds. Such bonds lead to stable molecules if they share
electrons in such a way as to create a noble gas configuration for
each atom.
Hydrogen gas forms the simplest covalent bond in the diatomic
hydrogen molecule. The halogens such as chlorine also exist as
diatomic gases by forming covalent bonds. The nitrogen and
oxygen which makes up the bulk of the atmosphere also exhibits
covalent bonding in forming diatomic molecules.
Polar Covalent Bonds
Covalent bonds in which the sharing of the electron pair is unequal, with the electrons spending more time around the
more nonmetallic atom, are called polar covalent bonds. In such a bond there is a charge separation with one atom
being slightly more positive and the other more negative, i.e., the bond will produce a dipole moment. The ability of an
atom to attract electrons in the presence of another atom is a measurable property called electronegativity.
Ionic Bonds
In chemical bonds, atoms can either transfer or share
their valence electrons. In the extreme case where one
or more atoms lose electrons and other atoms gain
them in order to produce a noble gas electron
configuration, the bond is called an ionic bond.
Typical of ionic bonds are those in the alkali halides
such as sodium chloride, NaCl.
Ionic bonding can be visualized with the aid of Lewis
diagrams.
Vocabulary Analysis: Read the article and come up with a list of content-based vocabulary (science terms where the
definition is either given or known) and Context based vocabulary (meaning of the word is inferred from the text)
Content-Based Vocabulary Words and Definitions
Context=Based Vocabulary Words and Definitions
Content-Based Vocabulary Words and Definitions
Context=Based Vocabulary Words and Definitions
Anticipated
Chemical Bond
Anticipated
Covalent bond
Ionic Bond
Valence
Polar Covalent
Diatomic molecule
Electronegativity
Noble gas configuration
Net
Contrast
Transfer
Bulk
Dipole moment
Shared
Extreme
Stable
Simplest
Exist
Create
Exhibit
Document Analysis: Paragraph 1
Central Question
How do atoms ‘bond’ to each other?
Guided Questions
1) What are chemical bonds?
Text Under Discussion
Chemical Bonding
Chemical compounds are formed by the
joining of two or more atoms. A stable
compound occurs when the total energy
of the combination has lower energy than
the separated atoms. The bound state
implies a net attractive force between the
atoms ... a chemical bond. The two
extreme cases of chemical bonds are:
Covalent bond: bond in which one or
more pairs of electrons are shared by two
atoms.
Ionic bond: bond in which one or more
electrons from one atom are removed
and attached to another atom, resulting
in positive and negative ions which
attract each other.
2) How is the creation of a stable compound similar to an electron
moving from the excited to ground state?
3) What would be a good analogy for covalent and ionic bonding? (ex;
life is like a box of chocolates, you never know what you’re gonna
get).
Covalent bonding is like….
Ionic bonding is like…
Document Analysis: Paragraph 2
Central Question
How do valence electrons affect covalent bonding?
Text Under Discussion
Guided Questions
1) Noble gases are not very reactive, as we have learned in
class. Explain the reason for this in terms of electron
configuration
2) Why is Hydrogen ‘content’ with only 2 electrons instead
of 8 like atoms in periods greater than 1?
Covalent Bonds
Covalent chemical bonds involve the sharing of a pair
of valence electrons by two atoms, in contrast to the
transfer of electrons in ionic bonds. Such bonds lead
to stable molecules if they share electrons in such a
way as to create a noble gas configuration for each
atom.
Hydrogen gas forms the simplest covalent bond in
the diatomic hydrogen molecule. The halogens such
as chlorine also exist as diatomic gases by forming
covalent bonds. The nitrogen and oxygen which
makes up the bulk of the atmosphere also exhibits
covalent bonding in forming diatomic molecules.
3) Explain in terms of electron configuration and sharing
electrons why the elements in group 17 (F, Cl, Br, and I)
of the periodic table exist as diatomic molecules.
Document Analysis: Paragraph 3
Central Question
How are polar covalent bonds different
than non-polar covalent bonds?
Guided Questions
1) Create an illustration for what is described in the first 2 sentences
Text Under Discussion
Polar Covalent Bonds
Covalent bonds in which the sharing of
the electron pair is unequal, with the
electrons spending more time around the
more nonmetallic atom, are called polar
covalent bonds. In such a bond there is a
charge separation with one atom being
slightly more positive and the other more
negative, i.e., the bond will produce a
dipole moment. The ability of an atom to
attract electrons in the presence of
another atom is a measurable property
called electronegativity.
2) Why do the electrons spend more time around the ‘more
nonmetallic’ atom than the less nonmetallic ones?
3) Water has polar covalent bonds between hydrogen and water.
Which element would have a slightly negative charge and which
would have a slightly positive charge. Explain, using evidence from
the text to support your prediction.
4) Using hints from the text, create a definition for what a dipole
moment is.
Document Analysis: Paragraph 4
Central Question
How can you predict if a bond will be ionic or covalent?
Guided Questions
1) The diagram shows different ionic compounds being
created. What type of elements are Na, Mg, and Ca.
Text Under Discussion
Ionic Bonds
In chemical bonds, atoms can either transfer or share
their valence electrons. In the extreme case where one
or more atoms lose electrons and other atoms gain
them in order to produce a noble gas electron
configuration, the bond is called an ionic bond.
Typical of ionic bonds are those in the alkali halides
such as sodium chloride, NaCl.
2) What happens to their electrons when they form Ionic
bonds?
3) What type of elements are Cl and O?
4)
What happens to their electrons when they form ionic
bonds?
Ionic bonding can be visualized with the aid of Lewis
diagrams.
5) Why would one atom transfer electrons to another
instead of sharing them? Think in terms of
electronegativity
6) Ionic compounds have extremely high melting points.
Why is this? (hint: think about attractive forces)
Name___________________________________________________________ Date______________ Grade________
Document Analysis: Essay Phase
Now that you have analyzed the document, you will be presented with a writing prompt to wrap up the analysis
by creating a document that demonstrates your ability to comprehend and apply what you read and analyzed.
Essay Prompt
- In order to accurately predict how two atoms will bond, electronegativity and electron configuration must
BOTH be considered.
Agree or disagree with this statement, using evidence from the reading as well as your prior knowledge to
support your argument.
Steps:
1) Read and interpret the essay prompt…what is being asked?
2) Brainstorm: put ideas down on paper as to how you want to tackle this essay. Facts, figures,
statements from the text and any prior knowledge from this course should be put down here. Pull
ideas out from your past knowledge and the text that will support your argument. Write them down.
These do not have to be in any particular order. It’s like pulling tools out of a toolbox that you know
you will need to do a repair job.
3) Outline: Organize your brainstormed ideas into a coherent and meaningful list that details the
points in the order you want to present them. Think of this as your brainstormed ideas being pieces
in a puzzle and you now have to put that puzzle together. Keep the rubric (on the other side of this
page) in mind as you gather your ideas together.
4) First Draft: Using your outline, create your argument. Fold a piece of paper in half vertically and
draw a vertical line along the crease. Write your first draft on the left side of the crease. Leave the
right side of the crease blank for now.
5) Proofread/Edit: Go through your essay and read it aloud under your breath. Does it make sense?
Where it doesn’t, or where there are glaring grammatical or spelling errors, make notes on the draft
for correction. Pair off with someone who has their essay completed, read your essays to each other
and see if they make sense to each of you. As you find areas you want to fix, cross out the
sentences you need to revise and rewrite them on the right side of the crease.
6) Final Draft: Rewrite your first draft into a final copy, paying close attention to the editing notes you
made in the previous step.
SCORE SHEET
Grading Rubric (what you earn will be highlighted when graded): Your earned points will be multiplied by 5 to
get a test grade out of 100.
Checklist:
Item
Attached to this cover page?
Brainstorm scrap sheet
Outline
First Draft with Edit Notes
Final Draft
Category
Introduction
(Organization)
Focus of Topic
(Content)
Support for Topic
(Content)
Conclusion
(Organization)
Grammar &
Spelling
(Conventions)
4
The introduction is
inviting, states the main
topic and position and
previews the structure of
the paper.
There is one clear, wellfocused topic. Main
idea stands out and is
supported by detailed
information.
Relevant, telling, quality
details give the reader
important information
that goes beyond the
obvious or predictable.
The conclusion is strong
and leaves the reader
with a feeling that they
understand what the
writer is “getting at”.
Writer makes no errors
in grammar or spelling
that distract the reader
from the content.
POINTS
3
2
1
The introduction clearly
states the main topic
and position and
previews the structure of
the paper, but is not
particularly inviting to the
reader.
Main idea is clear but
the supporting
information is general.
The introduction states
the main topic or
position but does not
adequately preview the
structure of the paper
nor is it particularly
inviting to the reader.
Main idea is somewhat
clear but there is a need
for more supporting
information.
There is no clear
introduction of the main
topic, position or
structure of the paper.
Supporting details and
information are relevant,
but one key issue is
unsupported.
Supporting details and
information are relevant,
but several key issues
are unsupported.
Supporting details and
information are typically
unclear or not related to
the topic.
The conclusion is
recognizable and ties up
almost all the loose
ends.
The conclusion is
recognizable but does
not tie up several loose
ends.
There is no clear
conclusion, the paper
just ends.
Writer makes 1-2 errors
in grammar or spelling
that distract the reader
from the content.
Writer makes 3-4 errors
in grammar or spelling
that distract the reader
from the content.
Writer makes more than
4 errors in grammar or
spelling that distract the
reader from the content.
The main idea is not
clear. There is a
seemingly random
collection of information.
Points/20:____________ X5 = pts/100:______________________________